13 May 1857|
|Died||16 September 1932
|Institutions||Presidency General Hospital, Calcutta
Liverpool School of Tropical Medicine
King's College Hospital
British War Office
Ministry of Pensions and National Insurance
Ross Institute and Hospital for Tropical Diseases
|Alma mater||St Bartholomew's Hospital Medical College
Society of Apothecaries
|Known for||Discovering that the malaria parasite is transmitted by mosquitoes|
|Notable awards||Nobel Prize in Physiology or Medicine (1902)
Albert Medal (1923)
Manson Medal (1929)
|Spouse||Rosa Bessie Bloxam|
|Children||2 sons and 2 daughters|
Sir Ronald Ross, KCB, FRS (13 May 1857 – 16 September 1932), was an Indian-born British medical doctor who received the Nobel Prize for Physiology or Medicine in 1902 for his work on malaria. His discovery of the malarial parasite in the gastrointestinal tract of mosquito led to the realisation that malaria was transmitted by mosquitoes, and laid the foundation for combating the disease. He was quite a polymath, writing a number of poems, published several novels, and composed songs. He was also an amateur artist and natural mathematician. He worked in the Indian Medical Service for 25 years. It was during his service that he made the groundbreaking medical discovery. After resigning from his service in India, he joined the faculty of Liverpool School of Tropical Medicine, and continued as Professor and Chair of Tropical Medicine of the institute for 10 years. In 1926 he became Director-in-Chief of the Ross Institute and Hospital for Tropical Diseases, which was established in honour of his works. He remained there until his death.
- 1 Early life and education
- 2 Career
- 3 Nobel Prize controversy
- 4 Personal life and death
- 5 Books
- 6 Literary works
- 7 Awards and recognitions
- 8 See also
- 9 References
- 10 Further reading
- 11 External links
Early life and education
Ronald Ross was born in Almora in present day Uttarakhand in India, the eldest of ten children of Sir Campbell Claye Grant Ross, General of the British Indian Army, and Matilda Charlotte Elderton. At age eight he was sent to England to live with his aunt and uncle on the Isle of Wight. He attended elementary schools at Ryde, and for secondary education he was sent to a boarding school at Springhill, near Southampton, in 1869. From his early childhood he developed passion for poetry, music, literature and mathematics. At fourteen years of age he won a prize for mathematics, a book titled Orbs of Heaven which sparked his interest in mathematics. At sixteen he secured first position in the Oxford and Cambridge local examination in drawing. Although he vowed to become a writer, he joined St Bartholomew's Hospital Medical College in London, in 1874, following his father's wish. Not fully committed, he spent most of his time composing music, and writing poems and plays. He left in 1880. In 1879 he had passed the examinations for the Royal College of Surgeons of England, and he worked as a ship's surgeon on a transatlantic steamship while studying for the licenciate of the Society of Apothecaries. He qualified on second attempt in 1881, and after a four-month training at Army Medical School, he entered Indian Medical Service in 1881. Between June 1888 and May 1889 he availed study leave to obtain the Diploma in Public Health from the Royal College of Physicians and Royal College of Surgeons, and took a course in bacteriology under Professor E. E. Klein.
Ronald Ross embarked for India on 22 September 1881 on the troopship Jumma. Between 1881 and 1894 he was variously posted in Madras, Burma, Baluchistan (now in Pakistan), Andaman Islands, Bangalore, and Secunderabad. In 1883, he was posted as the Acting Garrison Surgeon at Bangalore during which he noticed the possibility of controlling mosquitoes by limiting their access to water. In March 1894 he had his home leave and went to London with his family. On 10 April 1894 he met Patrick Manson, his mentor, for the first time. Manson introduced him to the real problems in malaria research. Manson always had a firm belief that India was the best place for the study. Ross returned to India on P&O Ferries' Ballaarat on 20 March 1895 and landed in Secunderabad on 24 April. Even before his luggage was cleared in the custom office, he went straight for Bombay Civil Hospital, looking for malarial patients and started making blood films.
Discovery of malaria vector
Ross made his first important step in May 1895 when he observed the early stages of malarial parasite inside a mosquito stomach. However, his enthusiasm was interrupted as he was deployed to Bangalore to investigate an outbreak of cholera. Bangalore had no regular cases of malaria. He confided to Manson stating, "I am thrown out of employment and have 'no work to do'." But in April he had a chance to visit Sigur Ghat near the hill station of Ooty, where he noticed a mosquito on the wall in a peculiar posture, and for this he called it "dappled-winged" mosquito, not knowing the species. In May 1896, he was given a short leave that enabled him to visit a malaria-endemic region around Ooty. In spite of his daily quinine prophylaxis, he was down with severe malaria three days after his arrival. In June he was transferred to Secunderabad. After two years of research failure, in July 1897, he managed to culture 20 adult “brown” mosquitoes from collected larvae. He successfully infected the mosquitoes from a patient named Husein Khan for a price of 8 annas (one anna per blood-fed mosquito!). After blood-feeding, he dissected the mosquito and found an "almost perfectly circular" cell from the gut, which was certainly not of the mosquito. (This discovery was published in 18 December 1897 issue of British Medical Journal.) On 20 August he confirmed the presence of the malarial parasite inside the gut of mosquito, which he originally identified as "dappled-wings" (which turned out to be species of the genus Anopheles). The next day, on 21 August, he confirmed the growth of the parasite in the mosquito. In the evening he composed the following poem for his discovery (originally unfinished, sent to his wife on 22 August, and completed a few days later):
This day relenting God
Hath placed within my hand
A wondrous thing; and God
Be praised. At His command,
Seeking His secret deeds
With tears and toiling breath,
I find thy cunning seeds,
O million-murdering Death.
I know this little thing
A myriad men will save.
O Death, where is thy sting?
Thy victory, O Grave?
Discovery of malaria transmission
In September 1897, Ross was transferred to Bombay, from where he was subsequently sent to a malaria-free Kherwara in Rajputana (now Rajasthan). Frustrated of lack of work he threatened to resign from service as he felt that it was a death blow to his pursuit. It was only on the representation of Patrick Manson, that the government arranged for his continued service in Calcutta on a "special duty". On 17 February 1898 he arrived in Calcutta (now Kolkata), to work in the Presidency General Hospital. He immediately carried out research in malaria and kala azar, for which he was assigned. He was given the use of Surgeon-Lieutenant-General Cunningham’s laboratory for his research. He had no success with malarial patients because they were always immediately given medication. He built a bungalow with a laboratory at Mahanad village, where he would stay from time to time to collect mosquitoes in and around the village. He employed Mahomed (or Muhammed) Bux, Purboona (who deserted him after the first payday), and Kishori Mohan Bandyopadhyay as laboratory assistants. As Calcutta was not a malarious place, Manson persuaded him to use birds, as being used by other scientists such as Vasily Danilewsky in Russia and William George MacCallum in America. Ross complied but with a complaint that he "did not need to be in India to study bird malaria". By March he began to see results on bird parasites, very closely related to the human malarial parasites. Using more convenient model of birds, by July 1898 he established the importance of mosquitoes as intermediate hosts in avian malaria. On 4 July he discovered that the salivary gland was the storage sites of malarial parasites in the mosquito. By 8 July he was convinced that tha parasites are released from the salivary gland during biting. He later demonstrated the transmission of malarial parasite from mosquitoes (in this case Culex species) to healthy birds from an infected one, thus, establishing the complete life cycle of malarial parasite.
In September 1898 he went to southern Assam in (northeast India) to study an epidemic of kala azar. He was invited to work there by Dr Graham Col Ville Ramsay, the second Medical Officer of the Labac Tea Estate Hospital. (His microscope and medicals tools are still preserved, and his sketches of mosquitoes are still on display at the hospital.) However, he utterly failed as he believed that the kala azar parasite (Leishmania donovani, the very scientific name he later gave in 1903) was transmitted by a mosquito, which he refers to as Anopheles rossi. (It is now known that kala azar is due to sandfly.)
In 1899, Ross resigned from Indian Medical Service and went to England to join the faculty of the Liverpool School of Tropical Medicine as lecturer. He continued to work on prevention of malaria in different parts of the world, including West Africa, the Suez Canal zone, Greece, Mauritius, Cyprus, and in the areas affected by the First World War. He also initiated organisations, which proved to be well established, for fighting malaria in India and Sri Lanka. He was appointed as Professor and Chair of Tropical Medicine of the Liverpool School of Tropical Medicine in 1902, which he held up to 1912. In 1912 he was appointed Physician for Tropical Diseases at King's College Hospital in London, and simultaneously hold the Chair of Tropical Sanitation in Liverpool. He remained in these posts until 1917 when he became (honorary) Consultant in Malariology in British War Office. Between 1918 ans 1926 he worked as Consultant in Malaria in the Ministry of Pensions and National Insurance.
Ross developed mathematical models for the study of malaria epidemiology, which he initiated in his report on Mauritius in 1908. He elaborated the concept in his book The Prevention of malaria in 1911 and further elaborated in a more generalised form in scientific papers published by the Royal Society in 1915 and 1916. These papers represented a profound mathematical interest which was not confined to epidemiology, but led him to make material contributions to both pure and applied mathematics.
Ross Institute and Hospital for Tropical Diseases
The Ross Institute and Hospital for Tropical Diseases was founded in 1926 and established at Bath House, a grand house with keeper's lodge and large grounds adjacent to Tibbet's Corner at Putney Heath. The hospital was opened by the then Prince of Wales, the future King Edward VII. Ross assumed the post of Director-in-Chief until his death. The institute was later incorporated into the London School of Hygiene & Tropical Medicine in Keppel Street. Bath House was later demolished and mansion flats built on the property. In memory of its history and owner the block was named Ross Court. Within the grounds an older dwelling, Ross Cottage, remains.
Nobel Prize controversy
Ronald Ross was awarded Nobel Prize basically for his discovery of the life cycle of malarial parasite, although he himself considered his epidemiological mathematics as a much more valuable contribution. He did not build his concept of malarial transmission in humans, but in birds, nor did he identify the exact species of mosquitoes (being not a zoologist, Ross simply described as "grey mosquito with dappled wings"). In 1897, an Italian physician and zoologist Giovanni Battista Grassi, along with his colleagues, had established the developmental stages of malaria parasites in anopheline mosquitoes; and they described the complete life cycles of P. falciparum, P. vivax and P. malariae the following year. When the 1902 Nobel Prize for Physiology or Medicine was considered, the Nobel Committee initially opined the prize to be shared between Ross and Grassi. Then Ross made a defamatory campaign accusing Grassi of deliberate fraud, calling him "a mountebank, a cheap crook, a parasite who survived on the ideas of others." Grassi responded with equally strong polemic. The weight of favour ultimately fell on Ross, largely upon the influences of Robert Koch, the appointed "neutral arbitrator" in the committee; as reported, "Koch threw the full weight of his considerable authority in insisting that Grassi did not deserve the honor". Ross was definitely the first to show that malarial parasite was transmitted by the bite of infected mosquitoes, in his case the avian Plasmodium relictum, which is rather quite a harmless parasite. But Grassi's work was much more directly relevant to human health as he demonstrated that human malarial parasites were incriminated only by female Anopheles. Indeed, it was Grassi who identified the species correctly, Anopheles claviger, and in 1898 who first established the complete life cycle of P. falciparum, the first human malarial parasite for which the entire cycle was determined.
Personal life and death
Ronald Ross was noted to be eccentric and egocentric, described as an "impulsive man". His professional life appeared to be in constant feud with his students, colleagues and fellow scientists. His personal vendetta with G.B. Grassi became a legendary tale in science. He was openly envious of his mentor Patrick Manson's affluence from private practices. This was largely been due to his own ineptitude to compete with other doctors. His Memories of Sir Patrick Manson (1930) was a direct attempt to belittle Manson's influences on his works on malaria. He hardly had good ties with the administration of Liverpool School of Tropical Medicine, constantly whining of being underpaid. He resigned twice, and was eventually discharged without any pension.
Ross was frequently embittered by lack of government support (what he called "administrative barbarism") for scientists in medical research. In 1928 he advertised his papers for sale in Science Progress, with a statement that the money was for financial support of his wife and family. Lady Houston bought them for £2000, and offered them to the British Museum, which turned her down for various reasons. The papers are now preserved by the London School of Hygiene and Tropical Medicine and the Royal College of Physicians and Surgeons of Glasgow.
Ross married Rosa Bessie Bloxam in 1889. They had two daughters, Dorothy (1891–1947) and Sylvia (1893–1925), and two sons, Ronald Campbell (1895–1914) and Charles Claye (1901–1966). His wife died in 1931. Ronald and Dorothy pre-deceased him too: Ronald was killed at the Battle of Le Cateau on 26 August 1914. Ross died at the hospital of his namesake after a long illness and asthma attack. He was buried at the nearby Putney Vale Cemetery, next to his wife.
- Report on Cholera, General Sanitation, and the Sanitary Department and Regulations, in the C. & M. Station of Bangalore (1896)
- Report on the Cultivation of Proteosoma Labbé, in Grey Mosquitoes (1898). Digitised version available from National Library of Scotland.
- Report on the Nature of Kala-azar (1899). Digitised version available from National Library of Scotland.
- Malarial Fever: Its Cause, Prevention and Treatment; Containing Full Details for the Use of Travellers, Sportsmen, Soldiers, and Residents in Malarious Places (1902)
- First Progress Report of the Campaign Against Mosquitoes in Sierra Leone (with Charles Wilberforce Daniels) (1902)
- Notes on the Parasites of Mosquitoes Found in India Between 1895 and 1899
- Hygiene for Indian Scholars
- Note on the Bodies Recently Described by Leishman and Donovan (1903)
- Further Notes on Leishman's Bodies (1903)
- Report on Malaria at Ismailia and Suez (1903)
- Leishmania Donovani Found in Kala-azar (1904)
- Researches on Malaria (1905)
- Note on a Flagellate Parasite Found in Culex Fatigans (1906)
- Malaria in Greece (1909)
- Missionaries and the Campaign Against Malaria (1910)
- A Case of Sleeping Sickness Studied by Precise Enumerative Methods: Regular Periodical Increase of the Parasites Disclosed (with David Thomson) (1910)
- Discussion on the Treatment of Malaria (1918)
- Mosquitoes and Malaria in Britain (1918)
- Suggestions for the Care of Malaria Patients (1919)
- Observations on malaria (1919)
- Memoirs, with a Full Account of the Great Malaria Problem and Its Solution (1923)
- Malaria-control in Ceylon Plantations (1926)
- Solid Space-algebra: The Systems of Hamilton and Grassmann Combined (1929)
- A Summary of Facts Regarding Malaria Suitable for Public Instruction (with Malcolm Watson) (1930)
- Memories of Sir Patrick Manson (1930)
- The solution of equations by iteration (with William Stott) (1930)
- A Priori Pathometry (with Hila Phobe Hudson) (1931)
- Mosquito Brigades and How to Organise Them ISBN 978-1-2905-5311-7
Ross was a prolific writer. He habitually wrote poems on most of the important events in his life. His poetic works gained him wide acclaim and they reflect his medical service, travelogue, philosophical and scientific thoughts. Many of his poems are collected in his Selected Poems (1928) and In Exile (1931). Some of his notable books are The Child of Ocean (1899 and 1932), The Revels of Orsera, The Spirit of Storm, Fables and Satires (1930), Lyra Modulatu (1931), and five mathematical works (1929–1931). He also compiled an extensive account The Prevention of Malaria in 1910 and another Studies on Malaria in 1928. He published his autobiography Memoirs, with a Full Account of the Great Malaria Problem and its Solution (547 pages long) in 1923. He carefully saved virtually everything about himself: correspondence, telegrams, newspaper cuttings, drafts of published and unpublished material, and all manner of ephemera.
Awards and recognitions
Ronald Ross was awarded the Nobel Prize for Physiology or Medicine in 1902 "for his work on malaria, by which he has shown how it enters the organism and thereby has laid the foundation for successful research on this disease and methods of combating it".
In 1901 he was elected a Fellow of the Royal College of Surgeons and also of the Royal Society, of which he became Vice-President from 1911 to 1913. In 1902 he was appointed a Companion of the Most Honourable Order of the Bath by King Edward VII. In 1911 he was promoted to the rank of Knight Commander of the same Order. He was also decorated with the title Officer of the Order of Leopold II of Belgium.
Ross received honorary membership of learned societies of most countries in Europe, and elsewhere. He got an honorary M.D. degree in Stockholm in 1910 at the centenary celebration of the Caroline Institute and his 1923 autobiography Memoirs was awarded that year's James Tait Black Memorial Prize. While his vivacity and single-minded search for truth caused friction with some people, he enjoyed a vast circle of friends in Europe, Asia and the United States who respected him for his personality as well as for his genius.
In India, Ross is remembered with great respect as a result of his work on malaria, the deadly epidemic which used to claim thousands of lives every year. There are roads named after him in many Indian towns and cities. In Calcutta the road linking Presidency General Hospital with Kidderpore Road has been renamed after him as Sir Ronald Ross Sarani. Earlier this road was known as Hospital Road. In his memory, the regional infectious disease hospital at Hyderabad was named Sir Ronald Ross Institute of Tropical and Communicable Diseases. The building where he worked and actually discovered the malarial parasite, located in Secunderabad near the Begumpet Airport, is a declared a heritage site and the road leading up to the building is named Sir Ronald Ross Road.
In 2010 the University of Liverpool has named its new biological science building "The Ronald Ross Building" in his honour. His grandson David Ross inaugurated it. The building is home to the university's facility for the Institute of Infection and Global Health.
- N., G. H. F. (1933). "Sir Ronald Ross. 1857–1932". Obituary Notices of Fellows of the Royal Society 1 (2): 108–115. doi:10.1098/rsbm.1933.0006.
- Rajakumar, K; Weisse, M (1999). "Centennial year of Ronald Ross' epic discovery of malaria transmission: an essay and tribute.". Southern Medical Journal 92 (6): 567–71. doi:10.1097/00007611-199906000-00004. PMID 10372849.
- "Ross and the Discovery that Mosquitoes Transmit Malaria Parasites". Centers for Disease Control and Prevention. 8 February 2010. Retrieved 31 January 2014.
- "Sir Ronald Ross (1857–1932)". Dr. B.S. Kakkilaya's Malaria Web Site. Retrieved 31 January 2014.
- "Biography of Sir Ronald Ross". London School of Hygiene & Tropical Medicine. Retrieved 31 January 2014.
- Lavery, Marck Bryan. "Malaria Wars Episode MDCCCXCVIII: Ronald Ross and the Great Malaria Problem". evolve360. Retrieved 9 February 2014.
- Ross, R (1897). "On some Peculiar Pigmented Cells Found in Two Mosquitos Fed on Malarial Blood". British Medical Journal 2 (1929): 1786–8. doi:10.1136/bmj.2.1929.1786. PMC 2408186. PMID 20757493.
- Sinden, Robert E. "Malaria, mosquitoes and the legacy of Ronald Ross". World Health Organization. Retrieved 31 January 2014.
- Scott, M. P. (007). "Developmental genomics of the most dangerous animal". Proceedings of the National Academy of Sciences 104 (29): 11865–11866. doi:10.1073/pnas.0704795104. PMC 1924572. PMID 17620616.
- Mackay, Alan L. (2001) . A Dictionary of Scientific Quotations (2, Reprinted ed.). Bristol: IOP Publishing Ltd. pp. 209–210. ISBN 9780750301060.
- Dutta, A. (2009). "Where Ronald Ross (1857–1932) worked: the discovery of malarial transmission and the Plasmodium life cycle". Journal of Medical Biography 17 (2): 120–122. doi:10.1258/jmb.2009.009004. PMID 19401518.
- Ross, Ronald (1898). Report on the cultivation of protesoma, Labbé, in grey mosquitoes. Calcutta: Superintendent of Govt. Printing. pp. 1–2.
- Katz, FF (1997). "On the centenary of Sir Ronald Ross's discovery of the role of the mosquito in the life cycle of the malaria parasite.". Journal of Medical Biography 5 (4): 200–4. doi:10.1177/096777209700500403. PMID 11619711.
- Bynum, WF (1999). "Ronald Ross and the malaria-mosquito cycle.". Parassitologia 41 (1–3): 49–52. PMID 10697833.
- Dutta, A (2009). "Where Ronald Ross (1857–1932) worked: the discovery of malarial transmission and the Plasmodium life cycle.". Journal of Medical Biography 17 (2): 120–2. doi:10.1258/jmb.2009.009004. PMID 19401518.
- Cook, GC (1997). "Ronald Ross (1857–1932): 100 years since the demonstration of mosquito transmission of Plasmodium spp—on 20 August 1897.". Transactions of the Royal Society of Tropical Medicine and Hygiene 91 (4): 487–8. doi:10.1016/s0035-9203(97)90295-9. PMID 9373663.
- Capanna E (2012). "Grassi versus Ross: who solved the riddle of malaria?". International Microbiology 9 (1): 69–74. PMID 16636993.
- Sherman, Irwin (2008). Reflections on a century of malaria biochemistry. London: Academic. p. 5. ISBN 978-0080-9-2183-9.
- "Laboc Hospital – A Noble Prize Winner's Workplace". easternpanorama.in. Retrieved 11 July 2013.
- "My experiences in Panama / Sir Ronald Ross 1916". National Library of Medicine.
- "1920 History Timeline | London School of Hygiene & Tropical Medicine | LSHTM". Timeline.lshtm.ac.uk. Retrieved 2 December 2012.
- Baccetti B (2008). "History of the early dipteran systematics in Italy: from Lyncei to Battista Grassi". Parasstologia 50 (3–4): 167–172. PMID 20055226.
- Esch GW (2007). Parasites and Infectious Disease: Discovery by Serendipity and Otherwise. Cambridge University Press. pp. 137–138. ISBN 978-1-1394-6-4109.
- Cook G (2007). Tropical Medicine: An Illustrated History of The Pioneers. Academic Press. pp. 93–97. ISBN 978-0080-5-5939-1.
- McCallum, Jack E. (2007). Military Medicine: From Ancient Times to the 21st Century (1st ed. ed.). Santa Barbara: Abc-Clio. pp. 273–274. ISBN 978-1-8510-9693-0.
- W. F. Bynum. "Ronald Ross: Malariologist and Polymath: A Biography". Project MUSE. Retrieved 9 February 2014.
- "Ross, Sir Ronald (1857–1932), surgeon : GB 250 RCPSG 9". Retrieved 10 April 2014.
- Sherborne School Book of Remembrance on Flickr
- "Ronald Ross – Facts". Nobel Media AB. Retrieved 31 January 2014.
- "World Mosquito Day". Malaria No More UK. Retrieved 31 January 2014.
- "Manor Park Residences". University of Surrey.
- "Ronald Ross Primary School – Home". Ronaldross.org.uk. 22 November 2012. Retrieved 2 December 2012.
- "Sir Ronald Ross Institute Of Parasitoloy". Osmania.ac.in. Retrieved 2 December 2012.
- "Opening of The Ronald Ross Building". Institute of Infection and Global Health, University of Liverpool. 10 October 2010. Retrieved 31 January 2014.
- Ross, Ronald (2011) . Memoirs, with a full account of the great malaria problem and its solution. South Carolina: Nabu Press (originally John Murray, London). ISBN 978-1179199481.
- de Kruif, Paul (1996) . Microbe Hunters. San Diego: A Harvest Book. pp. 256–285. ISBN 978-0-15-602777-9.
- Malcolm Watson (1930). Ronald Ross, 1857–1932. Reprinted from Science Progress.
- James Oram Dobson (1934). Ronald Ross, dragon slayer: a short account of a great discovery and of the man who made it. Student Christian Movement Press, p. 112
- Nye, Edwin R.; Gibson, Mary E. (1997). Ronald Ross : Malariologist and Polymath : a Biography. New York: St. Martin's Press, Inc. ISBN 0-312-16296-0.
- Bynum, William F.; Overy, Caroline (1998). The Beast in the Mosquito: the Correspondence of Ronald Ross and Patrick Manson. Amsterdam: Rodopi. ISBN 978-9-0420-0731-4.
- Cook, G.C. (2007). Tropical Medicine an Illustrated History of the Pioneers. London: Academic Press. pp. 68–81. ISBN 978-0-08-055939-1.
|Wikimedia Commons has media related to Ronald Ross.|
- Unveiling of a 'Blue Plaque' memorial to Ross at the University of Liverpool's Johnston Laboratories where he had worked
- Commemorative inscription
- Anecdotes from Ronald Ross' life
- Royal Society citation (1901)
- Nobel Prize biography
- Ross and the Discovery that Mosquitoes Transmit Malaria Parasites
- Ross's three part paper on the theory of epidemics is available on the web
- Ross, R. (1916). "An Application of the Theory of Probabilities to the Study of a priori Pathometry. Part I". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 92 (638): 204–226. Bibcode:1916RSPSA..92..204R. doi:10.1098/rspa.1916.0007.
- Ross, R.; Hudson, H. P. (1917). "An Application of the Theory of Probabilities to the Study of a priori Pathometry. Part II". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 93 (650): 212. Bibcode:1917RSPSA..93..212R. doi:10.1098/rspa.1917.0014.
- Ross, R.; Hudson, H. P. (1917). "An Application of the Theory of Probabilities to the Study of a Priori Pathometry.--Part III". Proceedings of the Royal Society B: Biological Sciences 89 (621): 507. doi:10.1098/rspb.1917.0008.