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Sedevacantism (derived from the Latin words sedes or "seat", and vacans or "vacant") is the position, held by a minority of Traditionalist Catholics, that the present occupant of the papal see is not truly Pope and that, for lack of a valid Pope, the see has been vacant since the death of Pope Pius XII in 1958. A tiny number of these claim the vacancy actually goes back to the death of Pope Pius X in 1914.
Sedevacantists believe that Paul VI (1963–1978), John Paul I (1978), John Paul II (1978–2005), Benedict XVI (2005–2013), and Francis (2013–present) have been neither true Catholics nor true Popes, by virtue of allegedly having espoused the heresy of Modernism, or of having otherwise denied or contradicted solemnly defined Catholic dogmas. Some of them classify John XXIII (1958–1963) also as a Modernist antipope.
The term "sedevacantism" is derived from the Latin phrase sede vacante, which literally means "the seat being vacant", specifically in the context of the vacancy of the Holy See. This phrase is normally used between the death or resignation of a pope and the election of his successor. "Sedevacantism" as a term in English appears to date from the 1980s, though the movement itself is older.
Among those who maintain that the see of Rome, occupied by what they declare to be an illegitimate pope, was really vacant, some have chosen an alternative pope of their own, and thus in their view ended the vacancy of the see, and are known sometimes as "conclavists".
Early history 
One of the earliest proponents of sedevacantism was the American Francis Schuckardt. Although still working within the "official" Church in 1967, he publicly took the position in 1968 that the Holy See was vacant and that the Church that had emerged from the Second Vatican Council was no longer Catholic. An associate of his, Daniel Q. Brown, arrived at the same conclusion. In 1969, Brown received episcopal orders from an Old Catholic bishop, and in 1971 he in turn consecrated Schuckardt. Schuckardt founded a congregation called the Tridentine Latin Rite Catholic Church.
In 1970, a Japanese layman, Yukio Nemoto (1925–1988), created Seibo No Mikuni, a sedevacantist group. Another founding sedevacantist was Father Joaquín Sáenz y Arriaga, a Jesuit theologian from Mexico. He put forward sedevacantist ideas in his books The New Montinian Church (August 1971) and Sede Vacante (1973). His writings gave rise to the sedevacantist movement in Mexico, led by Sáenz, Father Moisés Carmona and Father Adolfo Zamora, and also inspired Father Francis E. Fenton in the U.S.
In the years following the Second Vatican Council other priests took up similar positions, including:
- Dominican theologian Fr. Michel Louis Guérard des Lauriers, who developed a thesis similar to sedevacantism called sedeprivationism in the 1970s.
- Several students at the Society of St. Pius X seminary at Econe in the early/mid-1970s –i.e. Daniel Dolan, Anthony Cekada and Donald Sanborn — reportedly sedevacantists in that period – were expelled, along with three other seminarians from the SSPX by Archbishop Marcel Lefebvre for holding the error.
- English priest Fr. Oswald Baker, who was a sedevacantist at least by 1982, and reportedly some time prior to that.
- American missionary Fr. Lucian Pulvermacher, who left the Roman Catholic Church in 1976 and in October 1998 was elected Pope of the conclavist "True Catholic Church" with the name of "Pius XIII".
Sedevacantism owes its origins to the rejection of the theological and disciplinary changes implemented following the Second Vatican Council (1962–1965). Sedevacantists reject this Council, on the basis of its documents on ecumenism and religious liberty, which they see as contradicting the traditional teachings of the Catholic Church and as denying the unique mission of Catholicism as the one true religion, outside of which there is no salvation. They also say that new disciplinary norms, such as the Mass of Paul VI, promulgated on April 3, 1969, undermine or conflict with the historical Catholic faith and are deemed heresies.
Other traditionalist Catholics recognize as legitimate the line of Popes leading to Pope Francis. Some of them hold that one or more of the most recent popes have held and taught unorthodox beliefs, but do not go so far as to say that they have been formal heretics or have been widely and publicly judged to be heretics. Sedevacantists, on the other hand, claim that the infallible Magisterium of the Catholic Church could not have decreed the changes made in the name of the Second Vatican Council, and conclude that those who issued these changes could not have been acting with the authority of the Catholic Church. Accordingly, they hold that Pope Paul VI and his successors left the true Catholic Church and thus lost legitimate authority in the Church. A formal heretic, they say, cannot be the Catholic Pope.
Sedevacantists defend their position using numerous arguments, including that particular provisions of canon law prevent a heretic from being elected or remaining as Pope. Paul IV's 1559 bull, Cum ex apostolatus officio, stipulated that a heretic cannot be elected pope, while Canon 188.4 of the 1917 Code of Canon Law provides that a cleric who publicly defects from the Catholic faith automatically loses any office he had held in the Church. A number of writers have engaged sedevacantists in debate on some of these points. Theologian Brian Harrison has argued that Pius XII's conclave legislation permitted excommunicated cardinals to attend, from which he argues that they could also be legitimately elected. Opponents of Harrison have argued that a phrase in Pius XII's legislation, "Cardinals who have been deposed or who have resigned, however, are barred and may not be reinstated even for the purpose of voting", though it speaks of someone deposed or resigned from the cardinalate, not of someone who may have incurred automatic excommunication but has not been officially declared excommunicated, means that, even if someone is permitted to attend, that does not automatically translate into electability.
There are estimated[by whom?] to be between several tens of thousands and more than two hundred thousands of sedevacantists worldwide, mostly concentrated in the United States, Canada, France, the UK, Italy, and Australia, but the actual size of the sedevacantist movement has never been accurately assessed. (See further the section on statistics in the article Traditionalist Catholic.) Catholic doctrine teaches the four marks of the true Church are that it is One, Holy, Catholic, and Apostolic. Sedevacantists base their claim to be the remnant Roman Catholic Church on what they see as the presence in them of these four "marks", absent, they say, in the Church since the Second Vatican Council. Their critics counter that sedevacantists are not one, forming numerous splinter groups, each of them in disagreement with the rest. Most sedevacantists hold the Holy Orders conferred with the present revised rites of the Catholic Church to be invalid due to defect both of intention and form. Because they consider the 1968 revision of the rite of Holy Orders to have invalidated it, they conclude that the great majority of the bishops listed in the Holy See's Annuario Pontificio, including Benedict XVI and Francis themselves, are in reality merely priests or even laymen.
Bishops and holy orders 
Catholic doctrine holds that any bishop can validly ordain any baptised man to the priesthood or to the episcopacy, provided that he has the correct intention and uses a doctrinally acceptable rite of ordination, whether or not he has official permission of any sort to perform the ordination, and indeed whether or not he and the ordinand are Catholics. Absent specified conditions, canon law forbids ordination to the episcopate without a mandate from the Pope, and both those who confer such ordination without the papal mandate and those who receive it are subject to excommunication.
In a specific pronouncement in 1976, the Congregation for the Doctrine of the Faith declared devoid of canonical effect the consecration ceremony conducted for the Palmarian Catholic Church by Archbishop Pierre Martin Ngô Đình Thục on December 31, 1975, though it refrained from pronouncing on its validity. This declaration also applied pre-emptively to any later ordinations by those who received ordination in the ceremony. Of those then ordained, seven who are known to have returned to full communion with Rome did so as laymen. When Archbishop Emmanuel Milingo conferred episcopal ordination on four men in Washington on September 24, 2006, the Holy See's Press Office declared that "the Church does not recognize and does not intend in the future to recognize these ordinations or any ordinations derived from them, and she holds that the canonical state of the four alleged bishops is the same as it was prior to the ordination." This denial of canonical status means Milingo had no authority to exercise any ministry.
However, Rev. Ciro Benedettini, of the Holy See Press Office, who was responsible for publicly issuing, during the press conference, the communique on Milingo, stated to reporters that any ordinations the excommunicated Milingo had performed prior to his laicization were "illicit but valid", while any subsequent ordinations would be invalid.
On June 11, 2011, the Pontifical Council for Legislative Texts issued a statement regarding episcopal consecrations in China, saying that the penalty of excommunication imposed by law on those who consecrate or are consecrated without a papal mandate "must be tempered or a penance employed in its place" when those involved in the intrinsically evil act are "coerced by grave fear, even if only relatively grave, or due to necessity or grave inconvenience". It recalled that absolution from the excommunication in question is reserved to the Holy See. Bishop Juan Ignacio Arrieta, Secretary of the Pontifical Council, explained that the statement applied to the bishops ordained by Milingo and Thuc, as well as to the Chinese cases.
The bishops who are or have been active within the sedevacantist movement can be divided into four categories:
- Bishops consecrated within the "official" Church who were subsequently persuaded to the sedevacantist position. To date, this category seems to consist of only two individuals, both now deceased: the Vietnamese Archbishop Thục (who, before his death in 1984, may have been reconciled to Pope John Paul II) and the Chicago-born Mgr. Alfredo F. Mendez, the former Bishop of Arecibo, Puerto Rico.
- Bishops whose lineages derive from the foregoing bishops, which essentially means the "Thục line" of bishops deriving from Archbishop Thục. While the "Thục line" is lengthy and complex, reportedly comprising 200 or more individuals, the sedevacantist community generally accepts and respects most of the 12 or so bishops following from the three or four final consecrations that the Archbishop performed (those of Bishops Guerard des Lauriers, Carmona, Zamora and Datessen). Bishop Mendez consecrated one priest to the episcopacy, Fr. Clarence Kelly of the Society of St. Pius V, who consecrated one further bishop. Many bishops in the "Thục line" have been associated with the conclavist Palmarian Catholic Church. On September 24, 1991, Father Pivarunas was consecrated a bishop at Mount Saint Michael by Bishop Moises Carmona. On November 30, 1993, Bishop Pivarunas conferred episcopal consecration to Father Daniel Dolan in Cincinnati, Ohio, and on May 11, 1999, he consecrated Martin Davila for the Union Catolica Treno to succeed Bishop Carmona.
- Bishops whose lineages derive from earlier schisms. A considerable number of sedevacantist bishops are said to derive from Bishop Carlos Duarte Costa, who in 1945 set up his own schismatic "Brazilian Catholic Apostolic Church". More numerous are those who have had recourse to the Old Catholic line of succession. Bishops of this category include Francis Schuckardt and others associated with him. The orders of the original Old Catholic Church are regarded by the Roman Catholic Church as valid, though no such declaration of recognition has been issued with regard to the several independent Catholic churches that claim to trace their episcopal orders to this church. Some shadow of doubt hovers over the validity of the orders received from these bishops, and the claimants have not received wide acceptance in the sedevacantist community, though most have at least some small congregation.
- Bishops whose orders are generally regarded as invalid through lack of proper lineage. Lucian Pulvermacher and Gordon Bateman of the small conclavist "True Catholic Church" fall into this category.
Against sedevacantism, mainstream Catholics advance arguments such as:
- According to Catholic doctrine, the Catholic Church is a visible identifiable body that is literally catholic, in the sense of universal ("for all people"). This is seen as incompatible with the sedevacantist claim that the true nature of the Catholic Church has been hidden from the world for half a century
- The 1870 Dogmatic Constitution Pastor Aeternus of the First Vatican Council reaffirmed that "it has always been necessary for every Church, e.g., the faithful throughout the world — to be in agreement with (the Roman Church) because of its preeminent authority" and that consequently the bishop whom the Church in Rome acknowledges as its head "is the successor of blessed Peter, the prince of the apostles, true vicar of Christ, head of the whole Church and father and teacher of all Christian people. To him, in blessed Peter, full power has been given by our lord Jesus Christ to tend, rule and govern the universal Church." This is seen as incompatible with the sedevacantist claim that the papal line of succession has been broken since 1958 (or 1963).
- Critics of sedevacantism argue this also means that the theory advanced by the seventeenth-century theologian and Doctor of the Church Robert Bellarmine that a pope who fell into heresy would automatically forfeit his office and could be formally deposed has been overruled by Church authority by Benedict XIV in "De Synodo Dioecesano" (10,1,5) and by the 1917 Code of Canon Law, Can. 2232, Par. 1, "A penalty that is latae sententiae, whether medicinal or punitive, holds for one who is aware of his own delict in both fora [i.e., public and private]; but prior to a declaratory sentence, the delinquent is excused from observing the penalty any time that he cannot observe it without infamy, and in the external forum no one can compel the observance of that penalty from him unless the delict is notorious, with due regard for Can. 2223, Par. 4." Sedevacantist appeals to Bellarmine's authority in this point accordingly could not be sustained, adding that Bellarmine envisaged that such a deposition, even if possible, could only be undertaken by a significant body of the Church including many bishops and cardinals, rather than by a few individuals.
- The Catholic doctrine of the indefectibility of the Church, which appeals to Christ's promise to the Apostle Peter in Matthew 16:18 ("You are Peter (the Rock), and on this rock I will build my church, and the gates of hell will not prevail against it") excludes the possibility that the Catholic bishops around the world and the Pope with whom they are in communion would succumb to heresy and fall from office.
- They claim sedevacantists wrongly treat certain papal statements of the past as if they were ex cathedra declarations.
- They claim sedevacantists fail to distinguish between matters of discipline — such as the use of Latin and of the Tridentine Mass — which can be reformed at any time, and infallible dogmatic teachings.
- They claim sedevacantists indulge in the logical fallacy of post hoc ergo propter hoc when they attribute problems that the Church has experienced in the Western world since the reforms of the Second Vatican Council to the reforms themselves rather than to the general decrease in religiosity in the West.
Sedevacantists advance counter-arguments, such as:
- They deny that they implicitly repudiate the dogma of papal infallibility as defined at the First Vatican Council, and maintain that, on the contrary, they are the fiercest defenders of this doctrine, since they teach that the Apostolic See of Peter, under the rule of a true Pope, cannot promulgate contradictory teachings.
- They argue that the Dogmatic Constitution Pastor aeternus concerns the permanence of the primacy of the Holy See over the universal church and condemns as heretical the propositions that the authority granted to St. Peter by Christ either was abolished after his death or devolved to the college of bishops, both positions that were argued by Orthodox theologians. The very purpose of the Constitution was to solemnly and dogmatically refute those errors. The perpetuity granted divinely to the Petrine ministry was not the constant occupation of that office but that the monarchical structure of the Church, with the Seat of Peter as its head, would never be abrogated and endure throughout history. It is this permanence which allows the Holy See to function as the point of unity even during papal interregnum.
- To rebut the accusation of denying the catholicity and indefectibility of the Church, they say that, between the death of every Pope and the election of his successor, there is a sede vacante period during which there is no visible Head of the Church, and — while mainstream Catholics hold that, according to the dogmatic constitution Pastor aeternus of the First Vatican Council, which speaks of "perpetual successors" in the pontificate, there must be, apart from such transitory periods, a perpetual presence of the Bishop of Rome, not merely of his office — that the absence of a Pope has become a long-term feature of the Church's structure.
- They claim that, during the 40-year Great Western Schism, although no one asserted the see of Rome to be vacant, there was great uncertainty about which of the two (eventually three) claimants was the true pontiff, with even canonized saints taking opposing sides in the controversy. In his 1882 book, The Relations of the Church to Society — Theological Essays, a Jesuit theologian, Father Edmund J. O'Reilly, wrote: "... not that an interregnum covering the whole period would have been impossible or inconsistent with the promises of Christ, for this is by no means manifest."
- Anthony Cekada, an assistant pastor of sedevacantist bishop Daniel Dolan, in his book Work of Human Hands, says that the Mass of Paul VI is invalid and moreover strips down or removes completely every prayer in the Latin Rite which covers subjects such as judgment, heaven and hell, Satan, et al., and suggests that their full-scale removal, if such were to happen, would contribute to a lack of self-discipline and eventual loss of faith and skepticism among Catholics, responding to the post hoc ergo propter hoc accusation above. He criticizes the Mass of Paul VI for what he calls its "Protestantizations", such as referring to the service as a "supper" with a "table" and "cup" instead of a "sacrifice" with an "altar" and "chalice", making the congregation, in his view, the center of worship instead of God, and so forth. He claims that the Mass of Paul VI uses a Modernist method of mixing traditional language with Protestant language to appeal to both sides, and thus falling into heresy, in the same way as the Church of England is said to be "both Catholic and Reformed". The observation about the use of the word "cup", rather than "chalice", concerned only the English translation in use from 1973 to 2011, which employed both terms. It does not concern the original Latin text of the Mass of Paul VI, translations into other languages, or the present English translation, which always uses the word "chalice".
- Cekada, Patrick Henry Omlor and Rama Coomaraswamy criticize what they consider the wholescale removal of prayers and revisions to the consecration of the Eucharist. Omlor has objected to pro vobis et pro multis being translated in an earlier English translation as "for you and for all", instead of "for you and for many" as in the present English translation. On this see pro multis. They have also said that the revision of the words of consecration of the wine invalidates the sacrament by moving the phrase mysterium fidei (in the English translation, "the mystery of faith"), from the middle of the formula of consecration of the wine to after it and changing its context from, they say, referring to the transubstantiated Sacrament to the mystery of Christ's death and resurrection.
- They claim that the new rites of ordination and consecration are invalid, for not explicitly endowing the priest with the power to "offer Mass for the living and the dead", but simply, they say, "to preside over the assembly of the people". (The new rite in fact prays: "May Jesus preserve you to sanctify the Christian people and to offer sacrifice to God".) Consequently, they regard Catholic priests ordained or consecrated as bishops since 1968, when the new rite came into use, as invalid, and they consider Pope Benedict XVI, who was consecrated a bishop in 1977 in the new rite, to be a mere priest, who cannot be the Bishop of Rome.
Sedevacantism appears to be centered in, and by far strongest in, the United States, and secondarily other English-speaking countries. Anthony Cekada has described the United States as a "sedevacantist bastion", contrasting it with France, where the non-sedevacantist SSPX has a virtual monopoly on the traditional Catholic movement.
- The Church of Jesus Christ Divine Physician, an international, independent, traditional, Catholic, mega church, organization. It's headquarters are located in Kensington, London, England.
- Most Holy Family Monastery, a sedevacantist community living in Fillmore, New York, under the headship of Michael (né Frederick) Dimond. Only Michael and his biological brother Peter (né Robert) Dimond write the contents of the website. They are most known for their rigid defense of Extra Ecclesiam nulla salus, and for harshly attacking other traditionalists and sedevacantists who they allege stray from the Church's Magisterium on the matter.
- Society of St. Pius V, formed when nine priests of the Society of St. Pius X split from that organization over a number of issues including using the liturgical reforms implemented under Pope John XXIII. The SSPV maintains that much of the hierarchy of the Roman Catholic Church no longer adheres to the Catholic faith but instead profess a new, or Conciliar religion. They regard the question of the legitimacy of the present hierarchy and the possibility that the Holy See is unoccupied to be unresolved. The SSPV does not impose sedevacantism as a morally binding teaching.
- The Archbishop Thục lines of episcopal succession
- Catholic Restoration, consisting of the founding members — dissenters from SSPV, such as Cekada, Dolan and Sanborn, together with newer priests who were trained in their seminary.
- Congregation of Mary Immaculate Queen
- Apostles of Infinite Love, founded by Michel Collin (actually conclavist).
- Ukrainian Orthodox Greek Catholic Church, who profess the Catholic faith, including the primacy of the Roman Pontiff, but have declared both Pope John Paul II and Pope Benedict XVI excommunicated, leaving the Holy See vacant.
See also 
- Rev. Richard J. Neuhaus. Catholic Matters: Confusion, Controversy, and the Splendor of Truth, p. 133 (Basic Books, 2007). ISBN 0-465-04935-4
- R. Scott Appleby, Right: Conservative Catholics in America (Indiana University Press 1995 ISBN 978-0-253-32922-6), p. 257
- Martin E. Marty, R. Scott Appleby, Fundamentalisms Observed (University of Chicago Press: 1994; ISBN 978-0-226-50878-8), p. 88
- Fr. Antony Cekada (2008). "The Nine vs. Lefebvre: We Resist You to Your Face" (PDF). Retrieved 2012-11-15.
- Francis Schuckardt
- PierLuigi Zoccatelli, "Seibo Seibo No Mikuni, a Catholic Apocalyptic Splinter Movement from Japan", 2000
- Thomas W. Case, "The Society of St. Pius X Gets Sick", Fidelity Magazine (October 2002)
- Patrick Madrid and Peter Vere, More Catholic Than the Pope: An Inside Look at Extreme Traditionalism, p. 169 (Our Sunday Visitor, Inc., 2004); ISBN 1-931709-26-2
- Frank K. Flinn, Encyclopedia of Catholicism, p. 566 (Facts on File, Inc., 2007); ISBN 978-0-8160-5455-8
- David Gibson, The Rule of Benedict: Pope Benedict XVI and His Battle with the Modern World, p. 355 (HarperCollins, 2007); ISBN 978-0-06-116122-3
- Martin E. Marty, R. Scott Appleby, Fundamentalisms Observed, p. 66 (The University of Chicago Press, 1991); ISBN 0-226-50878-1
- Daniel Wójcik, The End of the World As We Know It: Faith, Fatalism, and Apocalypse in America, p. 86 (New York University Press, 1997); ISBN 0-8147-9283-9
- canon 1013
- canon 1382
- "As for those who have already thus unlawfully received ordination or any who may yet accept ordination from these, whatever may be the validity of the orders (quidquid sit de ordinum validitate), the Church does not and will not recognize their ordination (ipsorum ordinationem), and will consider them, for all legal effects, as still in the state in which they were before, except that the… penalties remain until they repent" (Sacred Congregation for the Doctrine of the Faith, Decree Episcopi qui alios of September 17, 1976 — Acta Apostolicae Sedis 1976, page 623).
- See "Thục consecrations"
- Declaration in Italian and English
- Frances D'Emilio (December 18, 2009). "Vatican dismisses defiant archbishop from clergy". Boston Globe. Retrieved 2012-11-15.
- John L. Allen, Jr. (December 17, 2009). "Last act in the Milingo story?". Retrieved 2012-11-15.
- Jesús Colina (June 14, 2011). "Vatican Calls China's Illicitly Ordained to Examine Hearts". ZENIT News Agency. Retrieved 2012-11-15.
- See list and line of descent at Thục Consecrations
- Clarence Kelly (1997). The Sacred and the Profane. Round Top, NY: Seminary Press. p. 101. Retrieved 2012-11-15.
- See photos of consecration at http://www.stpiusvchapel.org/photos/consecration2/consecration2.html
- For the many who look to him as the origin of their episcopal orders see Costa Consecrations.
- The Church @ www.newadvent.org
- Pastor Aeternus
- What is Sedevacantism
- John Daly, "Fr. O'Reilly On The Idea Of A Long-Term Vacancy Of The Holy See", 1999
- St. Gertrude the Great website
- The phrase "Mass or Lord's Supper" is used exactly twice in the revised Missal: GIRM 17 and 27
- The phrase "the altar or the table of the Lord" is used once (GIRM 73), immediately after using the word "altar" on its own; "the eucharistic table" is used in GIRM 73 in the same sense as that in which the 1962 Missal used "table" in, for instance, the Code of Rubrics, 528
- The revised Missal uses the word "calix", which in the official English translation appears as "chalice", not as "cup"
- The word "sacrifice" appears 215 times in the revised Missal
- The word "altar" appear 345 times in the revised Missal
- The word "chalice" appears 177 times in the revised Missal
- For instance, the 1973 English translation had, immediately after the consecration, "He (the priest) shows the chalice to the people, places it on the corporal, and genuflects in adoration."
- Ordination of Deacons, Priests and Bishops, Chapter III: "Ordination of a Priest", p. 24
- Kevin Vaillancourt, "On the new ordination rite: the Holy Sacrifice of the Mass is not the only sacred rite changed since Vatican II"
- Cekada, The Nine vs. Lefebvre: We Resist You to Your Face (2008), p. 14 
- Most Holy Family Monastery
- A more comprehensive list of objections can be found at "Letter of 'the Nine' to Abp. Marcel Lefebvre," The Roman Catholic (May 1983)
- Decree of Establishment of the UOGCC
- Declaration of an excommunication upon Pope Benedict XVI and John Paul II
Sedevacantist sites 
- Sedevacante International[dead link]
- European Sodalitium Pianum
- Sedevacantist European Seminary
- Sedevacantism Reconsidered
- Evidence of sedevacantism
- The Aquinas site. Sedevacantist.com.
- Defense of Sedevacantism
- Novus Ordo Watch
- Fr Raphael Trytek
- Eclipse of the Church
- WFTS radio SSPV sermons, lectures, music
- Most Holy Family Monastery
- Traditional Catholic network
- list of sites
- Critique of sedevacantism by the SSPX
- Is that Chair Vacant? A dossier on sedevacantism by the Society of St. Pius X of Canada.
- Against Sedevacantism. Discussion with the Dimond Brothers by Robert Sungenis
- The insanity of sedevacantism by Robert Sungenis.
- White smoke? Valid Pope by Father Brian Harrison
- Do-It-Yourself Popes: the Wacky World of Sedevacantists (concerning strict sedevacantists as well as conclavists)
- A Refutation of the Heresy of Sedevacantism by I. Shawn McElhinney.
-  Refutations at Kelopi.net