Old Japanese (上代日本語, Jōdai Nihon-go) is the oldest attested stage of the Japanese language, recorded in documents from the Nara period (8th century). It became Early Middle Japanese in the succeeding Heian period, but the precise delimitation of the stages is controversial. Old Japanese was an early member of the Japonic family. No conclusive links to other language families have been proved.
Old Japanese was written using Chinese characters by using an increasingly-standardized and phonetic form that eventually evolved into man'yōgana. As is typical of Japonic languages, Old Japanese was primarily an agglutinative language with a subject–object–verb word order. However, Old Japanese was marked by a few phonemic differences from later forms, such as a simpler syllable structure and distinctions between several pairs of syllables that have been pronounced identically since Early Middle Japanese. The phonetic realization of these distinctions is uncertain.
Sources and dating
Old Japanese is usually defined as the language of the Nara period (710–794), when the capital was Heijō-kyō (now Nara). That is the period of the earliest connected texts in Japanese, the 112 songs included in the Kojiki (712). The other major literary sources of the period are the 128 songs included in the Nihon Shoki (720) and the Man'yōshū (c. 759), a compilation of over 4,500 poems. Shorter samples are 25 poems in the Fudoki (720) and the 21 poems of the Bussokuseki-kahi (c. 752). The latter has the virtue of being an original inscription, whereas the oldest surviving manuscripts of all the other texts are the results of centuries of copying, with the attendant risk of scribal errors. Prose texts are more limited but are thought to reflect the syntax of Old Japanese more accurately than verse texts do. The most important are the 27 Norito (liturgies) recorded in the Engishiki (compiled in 927) and the 62 Senmyō (imperial edicts) recorded in the Shoku Nihongi (797).
A limited number of Japanese words, mostly personal names and place names, are recorded phonetically in ancient Chinese texts, such as the "Wei Zhi" portion of the Records of the Three Kingdoms (3rd century AD), but the transcriptions by Chinese scholars are unreliable. The oldest surviving native inscriptions, dating from the 5th or early 6th centuries, include those on the Suda Hachiman Shrine Mirror, the Inariyama Sword, and the Eta Funayama Sword. Those inscriptions are written in Classical Chinese but contain several Japanese names that were transcribed phonetically using Chinese characters. Such inscriptions became more common from the Suiko period (592–628). Those fragments are usually considered a form of Old Japanese.
Of the 10,000 paper records kept at Shōsōin, only two, dating from about 762, are in Old Japanese. Over 150,000 wooden tablets (mokkan) dating from the late 7th and early 8th century have been unearthed. The tablets bear short texts, often in Old Japanese of a more colloquial style than the polished poems and liturgies of the primary corpus.
Artifacts inscribed with Chinese characters dated as early as the 1st century AD have been found in Japan, but detailed knowledge of the script seems not to have reached the islands until the early 5th century. According to the Kojiki and Nihon Shoki, the script was brought by scholars from Baekje (southwestern Korea). The earliest texts found in Japan were written in Classical Chinese, probably by immigrant scribes. Later "hybrid" texts show the influence of Japanese grammar, such as the word order (for example, the verb being placed after the object).
Chinese and Koreans had long used Chinese characters to write non-Chinese terms and proper names phonetically by selecting characters for Chinese words that sounded similar to each syllable. Koreans also used the characters phonetically to write Korean particles and inflections that were added to Chinese texts to allow them to be read as Korean (Idu script). In Japan, the practice was developed into man'yōgana, a complete script for the language that used Chinese characters phonetically, which was the ancestor of modern kana syllabaries. This system was already in use in the verse parts of the Kojiki (712) and the Nihon Shoki (720).
|'many clouds rising'|
This method of writing Japanese syllables by using characters for their Chinese sounds (ongana) was supplemented with indirect methods in the complex mixed script of the Man'yōshū (c. 759).
In man'yōgana, each Old Japanese syllable was represented by a Chinese character. Although any of several characters could be used for a given syllable, a careful analysis reveals that 88 syllables were distinguished in early Old Japanese, typified by the Kojiki songs:
|a 阿||ka 加,迦||ga 賀||sa 佐||za 邪||ta 多||da 陀||na 那||pa 波||ba 婆||ma 麻||ya 夜||ra 良||wa 和|
|i 伊||ki1 岐||gi1 芸||si 斯,志||zi 士||ti 知||di 遅||ni 爾,迩||pi1 比||bi1 毘||mi1 美||ri 理||wi 韋|
|ki2 紀||gi2 疑||pi2 斐||bi2 備||mi2 微|
|u 宇||ku 久||gu 具||su 須||zu 受||tu 都||du 豆||nu 奴||pu 布||bu 夫||mu 牟||yu 由||ru 流|
|e 亜||ke1 祁||ge1 牙||se 勢,世||ze 是||te 弖||de 傅||ne 泥||pe1 弊||be1 辨||me1 賣||ye 延||re 禮||we 恵|
|ke2 気||ge2 宜||pe2 閇||be2 倍||me2 米|
|o 淤,意||ko1 古||go1 胡,呉||so1 蘇||zo1 俗,蘇||to1 斗||do1 度||no1 怒||po 富,本||bo 煩||mo1 毛||yo1 用||ro1 漏,路||wo 袁,遠|
|ko2 許||go2 碁||so2 曾||zo2 叙||to2 登||do2 杼||no2 能||mo2 母||yo2 余,與||ro2 呂|
As in later forms of Japanese, the system has gaps where yi and wu might be expected. However, many syllables that have a modern i, e or o occurred in two forms, termed types A (甲, kō) and B (乙, otsu), denoted by subscripts 1 and 2 respectively in the above table. The syllables mo1 and mo2 are not distinguished in the slightly-later Nihon Shoki and Man'yōshū, reducing the syllable count to 87. Some authors also believe that two forms of po were distinguished in the Kojiki. All of these pairs had merged in the Early Middle Japanese of the Heian period.
The consonants g, z, d, b and r did not occur at the start of a word. Nor could a word begin with a bare vowel. The rare vowel i2 almost always occurred at the end of a morpheme. Most occurrences of e1, e2 and o1 were also at the end of a morpheme.
|Kindaichi, Miller, Ōno||i||ï||e||ë||o||ö|
|Frellesvig and Whitman||i||wi||ye||e||wo||o|
There is no consensus on the pronunciation of the syllables distinguished by man'yōgana. One difficulty is that the Middle Chinese pronunciations of the characters used are also disputed, and since the reconstruction of their phonetic values is partly based on later Sino-Japanese pronunciations, there is a danger of circular reasoning. Additional evidence has been drawn from phonological typology, subsequent developments in the Japanese pronunciation, and the comparative study of the Ryukyuan languages.
Old Japanese had open syllables of the form (C)V subject to additional restrictions:
- Words did not begin with r or the voiced obstruents b, d, z, and g, with the exception of a few loanwords.
- A bare vowel did not occur except for word-initially: vowel sequences were not permitted.
In 1934, Arisaka Hideyo proposed a set of phonological restrictions permitted in a single morpheme. Arisaka's Law states that -o2 was generally not found in the same morpheme as -a, -o1 or -u. Some scholars have interpreted that as a vestige of earlier vowel harmony, but it is very different from patterns that are observed in, for example, the Turkic languages.
The Chinese characters chosen to write syllables with the Old Japanese vowel a suggest that it was an open unrounded vowel /a/. The vowel u was a close back rounded vowel /u/, unlike the unrounded /ɯ/ of Modern Standard Japanese.
Several hypotheses have been advanced to explain the A/B distinctions made in man'yōgana. The issue is hotly debated, and there is no consensus. The widely accepted and traditional view, first advanced by Kyōsuke Kindaichi in 1938, is that there were eight pure vowels, with the type B vowels being more central than their type A counterparts. Others, beginning in the 1930s but more commonly since the work of Roland Lange in 1968, have attributed the type A/B distinction to medial or final glides /j/ and /w/. The diphthong proposals are often connected to hypotheses on pre-Old Japanese, but all exhibit an uneven distribution of glides.
|i||ï||e||ë||o||ö||Kindaichi (1938), Miller (1967)|
|ji||i||je||e||wo||o||Lange (1968, 1973)|
|i||wi||je||e||wo||o||Unger (1977), Frellesvig and Whitman (2008)|
The distinction between mo1 and mo2 was seen only in Kojiki and vanished afterwards. The distribution of syllables suggests that there may have once been *po1, *po2, *bo1 and *bo2. If that was true, a distinction was made between Co1 and Co2 for all consonants C except for w. Some take that as evidence that Co1 may have represented Cwo.
Most scholars derive the Old Japanese vowel system from an earlier four-vowel system, with the most common Old Japanese vowels a, u, i1 and o2 reflecting earlier *a, *u, *i and *ə respectively. Internal reconstruction suggests that the other, less common, Old Japanese vowels were derived from fusions of those vowels. For example, the place name take2ti is derived from a compound of taka- 'high' and iti 'market'. Another piece of evidence is that many nouns had different forms, depending on whether they were used independently or within compounds, such as sake2 'rice wine', which became saka- in compounds such as sakaduki 'saké cup'. In such cases, the bound form is considered basic, and the independent form may be explained by postulating a suffix *-i that later fused with the final vowel of the root. The following reductions are proposed:
- i2 < *ui: kami2/kamu- 'god, spirit', mi2/mu- 'body', nagi2/nagu- 'a calm'.
- i2 < *əi: ki2/ko2- 'tree', yomi2/yomo2- 'Hades'.
- e1 < *ia: sake1ri 'blooming' < saki1 'to bloom' + ari 'to be'.
- e1 < *iə: pe1ku (proper name) < pi1 'sun' + o2ki1 'put'.
- e2 < *ai: me2/ma- 'eye', ame2/ama- 'heaven', ame2/ama- 'rain', kage2/kaga- 'shade'.
- o1 < *ua: kazo1pu 'to count' < kazu 'number' + apu 'to combine'.
- o1 < *uə: sito1ri 'kind of native weaving' < situ 'native weaving' + ori 'weaving'.
There are also alternations suggesting e2 < *əi, such as:
- se2/so2- 'back', me2/mo2- 'bud'
Some authors believe that they belong to an earlier layer than i2 < *əi, but others reconstruct two central vowels *ə and *ɨ, which merged everywhere except before *i. Other authors attribute the variation to different reflexes in different dialects and note that *əi yields e in Ryukyuan languages.
Some authors also postulate *e and *o to account for word-final e1 and o1 respectively. A few alternations, as well as comparisons with Eastern Old Japanese and Ryukyuan languages, suggest that *e and *o also occurred in non-word-final positions at an earlier stage but were raised in such positions to i1 and u, respectively, in central Old Japanese. The mid vowels are also found in some early mokkan and in some modern Japanese dialects.
Miyake reconstructed the following inventory, in addition to a zero vowel-initial onset /∅/:
The voiceless obstruents /p, t, s, k/ had the voiced prenasalized counterparts /ᵐb, ⁿd, ⁿz, ᵑɡ/. Prenasalization was still present in the late 17th century (according to the Korean textbook Ch'ŏphae Sinŏ) and is found in some Modern Japanese and Ryukyuan dialects, but it has disappeared in Modern Japanese except for the intervocalic nasal stop allophone [ŋ] of /ɡ/. The sibilants /s/ and /ⁿz/ may have been palatalized before e and i.
Comparative evidence from Ryukyuan languages suggests that Old Japanese p continued an earlier voiceless bilabial stop *p. There is general agreement that word-initial p had become a voiceless bilabial fricative [ɸ] by Early Middle Japanese, as suggested by its transcription as f in later Portuguese works and as ph or hw in the Korean textbook Ch'ŏphae Sinŏ. In Modern Standard Japanese, it is romanized as h and has different allophones before various vowels. In medial position, it became [w] in Early Middle Japanese but has disappeared except before a. Many scholars argue that p had already lenited to [ɸ] by the Old Japanese period, but Miyake argues that it was still a stop.
Internal reconstruction suggests that the Old Japanese voiced obstruents, which always occurred in medial position, arose from the weakening of earlier nasal syllables before voiceless obstruents:
- b /ᵐb/ < *-mVp-, *-nVp-: e.g. abi1ki1 'trawling' < ami1 'net' + pi1ki1 'pull'.
- d /ⁿd/ < *-mVt-, *-nVt-: e.g. yamadi 'mountain path' < yama 'mountain' + mi1ti 'path'.
- z /ⁿz/ < *-mVs-, *-nVs-: e.g. the title murazi < mura 'village' + nusi 'master'.
- g /ᵑɡ/ < *-mVk-, *-nVk-.
In some cases, there is no evidence for a preceding vowel, which leads some scholars to posit final nasals at the earlier stage.
Some linguists suggest that Old Japanese w and y derive, respectively, from *b and *d at some point before the oldest inscriptions in the 6th century. Southern Ryukyuan varieties such as Miyako, Yaeyama and Yonaguni have /b/ corresponding to Old Japanese w, but only Yonaguni (at the far end of the chain) has /d/ where Old Japanese has y:
- ba 'I' and bata 'stomach' corresponding to Old Japanese wa and wata
- Yonaguni da 'house', du 'hot water' and dama 'mountain' corresponding to Old Japanese ya, yu and yama
- wa + ga + ipe1 → wagape1
- ake + u → aku
- to2ko2 + ipa → to2ki1pa
Elsewhere, the vowels appear to have fused:
- ko2 + i → ki2
Although modern Japanese dialects have pitch accent systems, they were usually not shown in man'yōgana. However, in one part of the Nihon Shoki, the Chinese characters appeared to have been chosen to represent a pitch pattern similar to that recorded in the Ruiju Myōgishō, a dictionary that was compiled in the late 11th century. In that section, a low pitch syllable was represented by a character with the Middle Chinese level tone, and a high pitch was represented by a character with one of the other three Middle Chinese tones. (A similar division was used in the tone patterns of Chinese poetry, which were emulated by Japanese poets in the late Asuka period.) Thus, it appears that the Old Japanese accent system was similar to that of Early Middle Japanese.
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As in later forms of Japanese, Old Japanese word order was predominantly subject–object–verb, with adjectives and adverbs preceding the nouns and verbs they modify and auxiliary verbs and particles consistently appended to the main verb.
Many Old Japanese pronouns had both a short form and a longer form with attached -re of uncertain etymology. If the pronoun occurred in isolation, the longer form was used.
With genitive particles or in nominal compounds, the short form was used, but in other situations, either form was possible.
- The first-person pronouns were a(re) and wa(re), were used for the singular and plural respectively, though with some overlap. The wa- forms were also used reflexively, which suggests that wa was originally an indefinite pronoun and gradually replaced a.
- The second-person pronoun was na(re).
- The third-person pronoun si was much less commonly used than the non-proximal demonstrative so2 from which it was derived.
- There were also an interrogative pronoun ta(re) and a reflexive pronoun o2no2.
In Early Middle Japanese, the non-proximal so- forms were reinterpreted as hearer-based (medial), and the speaker-based forms were divided into proximal ko- forms and distal ka-/a- forms, yielding the three-way distinction that is still found in Modern Japanese.
Old Japanese had a richer system of verbal suffixes than later forms of Japanese. Old Japanese verbs used inflection for modal and conjunctional purposes. Other categories, such as voice, tense, aspect and mood, were expressed by using optional suffixed auxiliaries, which were also inflected.
As in later forms of Japanese, Old Japanese verbs had a large number of inflected forms. In traditional Japanese grammar, they are represented by six forms (katsuyōkei, 活用形) from which all the others may be derived in a similar fashion to the principal parts used for Latin and other languages:
- Mizenkei (irrealis)
- This form never occurs in isolation but only as a stem to which several particles and auxiliaries are attached. Unger calls it a "pseudostem" because the purported inflection was originally an initial *a of the suffixes attached to that stem.
- Renyoukei (adverbial, infinitive)
- This form was used as the infinitive. It also served as a stem for auxiliaries expressing tense and aspect.
- Shushikei (conclusive, predicative)
- This form was used as the main verb concluding a declarative sentence. It was used also before modal extensions, final particles, and some conjunctional particles. The conclusive form merged with the attributive form by about 1600, but the distinction is preserved in the Ryukyuan languages and the Hachijōjima dialects.
- Rentaikei (attributive, adnominal)
- This form was used as the verb in a nominalized clause or a clause modifying a noun. It was also used before most conjunctional particles.
- Izenkei (realis, exclamatory, subjunctive)
- This form was used as the main verb in an exclamatory sentence or as the verb in an adverbial clause. It also served as a stem for the particles -ba (provisional) and -do (concessive).
- Meireikei (imperative)
- This form expressed the imperative mood.
This system has been criticized because the six forms are not equivalent, with one being solely a combinatory stem, three solely word forms, and two being both. It also fails to capture some inflected forms. However, five of the forms are basic inflected verb forms, and the system also describes almost all extended forms consistently.
Japanese verbs are classified into eight conjugation classes, each being characterized by different patterns of inflected forms. Three of the classes are grouped as consonant bases:
- Yodan (quadrigrade)
- This class of regular consonant-base verbs includes approximately 75% of verbs. The class is so named because the inflections in later forms of Japanese span four rows of a kana table, corresponding to four vowels. However, in Old Japanese, five different vowels were involved. The bases are almost all of the form (C)VC-, with the final consonant being p, t, k, b, g, m, s or r.
- Na-hen (n-irregular)
- The three n-base verbs form a class of their own: sin- 'die', -in- 'depart' and the auxiliary -(i)n- expressing completion of an action. They are often described as a "hybrid" conjugation because the adnominal and exclamatory forms followed a similar pattern to vowel-base verbs.
- Ra-hen (r-irregular)
- The irregular r-base verbs were ar- 'be, exist' and other verbs that incorporated it, as well as wor- 'sit', which became the existential verb or- in later forms of Japanese.
The distinctions between i1 and i2 and between e1 and e2 were eliminated after s, z, t, d, n, y, r and w.
There were five vowel-base conjugation classes:
- Shimo nidan (lower bigrade or e-bigrade)
- The largest regular vowel-base class ended in e2 and included approximately 20% of verbs.
- Kami nidan (upper bigrade or i-bigrade)
- This class of bases ended in i2 and included about 30 verbs.
- Kami ichidan (upper monograde or i-monograde)
- This class contains about 10 verbs of the form (C)ii-. Some monosyllabic i-bigrade verbs had already shifted to this class by Old Japanese, and the rest followed in Early Middle Japanese.
- Ka-hen (k-irregular)
- This class consists of the single verb ko2- 'come'.
- Sa-hen (s-irregular)
- This class consists of the single verb se- 'do'.
Early Middle Japanese also had a Shimo ichidan (lower monograde or e-monograde) category, consisting of a single verb kwe- 'kick', which reflected the Old Japanese lower bigrade verb kuwe-.
The bigrade verbs seem to belong to a later layer than the consonant-base verbs. Many e-bigrade verbs are transitive or intransitive counterparts of consonant-stem verbs. In contrast, i-bigrade verbs tend to be intransitive. Some bigrade bases also appear to reflect pre-Old-Japanese adjectives with vowel stems combined with an inchoative *-i suffix:
- *-a-i > -e2, e.g. ake2- 'redden, lighten' vs aka 'red'.
- *-u-i > -i2, e.g. sabi2- 'get desolate, fade' vs sabu- 'lonely'.
- *-ə-i > -i2, e.g. opi2- 'get big, grow' vs opo- 'big'.
Old Japanese adjectives were originally nominals and, unlike in later periods, could be used uninflected to modify following nouns. They could also be conjugated as stative verbs and were divided into two classes:
The second class had stems ending in -si, which differed only in the conclusive form, whose suffix -si was dropped by haplology. Adjectives of this class tended to express more subjective qualities. Many of them were formed from a verbal stem by the addition of a suffix -si, of uncertain origin.
Towards the end of the Old Japanese period, a more expressive conjugation emerged by adding the verb ar- 'be' to the infinitive, with the sequence -ua- reducing to -a-:
- 230 azuma uta 'eastern songs', making up volume 14 of the Man'yōshū,
- 93 (101 according to some authors) sakimori uta 'borderguard songs' in volume 20 of the Man'yōshū, and
- 9 songs in the Hitachi fudoki (recorded 714–718, but the oldest extant manuscripts date from the late 17th century and show significant corruption).
They record Eastern Old Japanese dialects, with several differences from central Old Japanese (also known as Western Old Japanese):
- There is no type A/B distinction on front vowels i and e, but o1 and o2 are distinguished.
- Pre-Old Japanese *ia yielded a in the east, where central Old Japanese has e1.
- The adnominal form of consonant-base verbs ended in -o1, but central Old Japanese had -u as in the conclusive form. A similar difference is preserved in Ryukyuan languages, suggesting that central Old Japanese had innovated by merging those endings.
- The imperative form of vowel-base verbs attached -ro2, instead of the -yo2 used in central Old Japanese.
- There was a group of distinctive negative auxiliaries, but they do not seem to be the source of the different negatives in the modern eastern and western Japanese dialects.
- Described as "The ancestor of modern Japanese. 7th–10th centuries AD." The more usual date for the change from Old Japanese to Middle Japanese is c. 800 (end of the Nara era).
- Readings are given in Baxter's transcription for Middle Chinese, omitting marking of tones, which are not relevant here.
- These are the characters most used in the Kojiki songs, except for go1 and zo1 from the Man'yōshū.
- Shibatani 1990, p. 119.
- Miyake 2003, p. 1.
- Miyake 2003, p. 17.
- Frellesvig 2010, p. 24.
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- Bentley 2001, p. 6.
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- Miyake 2003, p. 12.
- Miyake 2003, p. 66.
- Seeley 1991, pp. 55–56.
- Frellesvig 2010, p. 22.
- Miyake 2003, pp. 8–9.
- Seeley 1991, pp. 25–31.
- Shibatani 1990, p. 126.
- Seeley 1991, pp. 41–49.
- Miyake 2003, pp. 18–20, 28–40.
- Miyake 2003, pp. 1, 18, 22.
- Frellesvig 2010, p. 19.
- Seeley 1991, pp. 49–53.
- Miyake 2003, pp. 20, 24–27.
- Frellesvig 2010, pp. 17–20.
- Miyake 2003, pp. 49–51.
- Frellesvig 2010, pp. 26–27.
- Frellesvig 2010, pp. 28–29.
- Miyake 2003, p. 51.
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- Miyake 2003, p. 61.
- Miyake 2003, p. 84.
- Frellesvig 2010, p. 26.
- Frellesvig 2020.
- Frellesvig 2010, p. 34.
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- Miyake 2003, p. 2.
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- Miyake 2003, pp. 64–65.
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- Vovin 2010, pp. 32–36.
- Osterkamp 2017, pp. 46–48.
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- Shibatani 1990, p. 194.
- Miyake 2003, p. 74.
- Miyake 2003, pp. 71, 164–166.
- Miyake 2003, p. 73.
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- Miyake 2003, pp. 71–73.
- Shibatani 1990, p. 195.
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- Pellard 2020, pp. 7–11.
- Unger 2000, p. 666.
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- Unger 2000, p. 657.
- Miyake 2003, pp. 37–39.
- Shibatani 1990, pp. 122–123.
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- Frellesvig 2010, p. 138.
- Frellesvig 2010, p. 136.
- Frellesvig 2010, pp. 138–139.
- Frellesvig 2010, pp. 139–140.
- Frellesvig 2010, p. 141.
- Frellesvig 2010, pp. 140, 246–247.
- Shibatani 1990, p. 123.
- Frellesvig 2010, p. 53.
- Frellesvig 2010, p. 59.
- Frellesvig 2010, pp. 114–118.
- Frellesvig 2010, pp. 111–112.
- Unger 2000, p. 665.
- Frellesvig 2010, pp. 56–57.
- Frellesvig 2010, pp. 109–111.
- Frellesvig 2010, pp. 123–124, 133.
- Shibatani 1990, pp. 195, 207, 223–224.
- Frellesvig 2010, pp. 54–55.
- Frellesvig 2010, p. 133.
- Frellesvig 2010, p. 55.
- Frellesvig 2010, pp. 112–113.
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- Frellesvig 2010, p. 96.
- Frellesvig 2010, p. 115.
- Frellesvig 2010, p. 97.
- Frellesvig 2010, p. 105.
- Frellesvig 2010, pp. 101–103.
- Frellesvig 2010, pp. 54, 114.
- Frellesvig 2010, p. 106.
- Frellesvig 2010, pp. 107–108.
- Frellesvig 2010, pp. 227–228.
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- Kondō, Tsukimoto & Sugiura 2005, p. 41.
- Omodaka 1967, pp. 37–38.
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- Whitman 2008, p. 164.
- Frellesvig 2010, p. 119.
- Whitman 2008, p. 165.
- Vovin 2020, pp. 373–383.
- Frellesvig 2010, pp. 79–80.
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- Bentley 2012, p. 198.
- Frellesvig 2010, p. 82.
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- Frellesvig 2010, p. 91.
- Bentley 2001, p. 138.
- Frellesvig 2010, p. 235.
- Vovin 2020, pp. 386–389.
- Vovin 2020, pp. 11–14.
- Miyake 2003, p. 159.
- Frellesvig 2010, pp. 23–24, 151.
- Kupchik 2011, p. 1.
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