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FamilySearch: Richard Thornton. https://www.familysearch.org/en/tree/person/details/MTWL-BMP AND https://www.familysearch.org/ark:/61903/1:1:QV2Y-BDY9?lang=en
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Mendelssohn, S. South African bibliography. London, 1910.
National Automated Archival Information Retrieval System (NAAIRS). http://national.archives.gov.za/naairs.htm Documents relating to Thornton, Richard.
Richard Thornton. Retrieved on 27 January 2021 from https://peoplepill.com/people/richard-thornton-1
Royal Society of London. Catalogue of scientific papers [1800-1900]. London: Royal Society, 1867-1925.
Venter, R.J. Bibliography of regional meteorological literature. Vol. 1. Southern Africa, 1486-1948. Pretoria: Weather Bureau, 1949.