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FamilySearch: Leopold Marquard. https://ancestors.familysearch.org/en/K466-X79/leopold-marquard-1826-1897
Fourcade, H.G. & Whittingdale, W. Correspondence: Mr Leonard Marquard. South African Survey Journal, 1930, Vol. 3, pp. 359-362.
Kirby, P.R. The Heerenlogement and its visitors. South African Journal of Science, 1942, Vol. 38, pp. 352-386.
Leopold Marquard. The system of coordinates applied to land surveying. Advertisement
retrieved from https://play.google.com/store/books/details/The_System_of_Coordinates_Applied_to_Land_surveyin?id=3n5aAAAAcAAJ&hl=en_US
on 2018-9-1.
Liebenberg, E.C. Die topografiese kartering van Suid-Afrika, 1879-1972; 'n histories-geografiese ontleding. MA-verhandeling in Geografie, Universiteit van Suid-Afrika, 1973.
Malherbe, D.F. du T. Family register of the South African nation (3rd ed.) Stellenbosch: Tegniek, 1966.
National Automated Archival Information Retrieval System (NAAIRS). http://www.national.archives.gov.za/naairs.htm Documents relating to Marquard, Leopold / Marquard, L.
Ritchie, W. The history of the South African College, 1829-1918 (list of alumni). Cape Town: T. Maskew Miller, 1918.
Rosenthal, E. Southern African dictionary of national biography. London: F. Warne, 1966.
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