(en) (7 maart 1931). Obituary notices. Proceedings of the Royal Society of London. Series B, Containing Papers of a Biological Character107 (754). ISSN: 0950-1193. DOI: 10.1098/rspb.1931.0012.
(en) (7 maart 1931). Obituary notices. Proceedings of the Royal Society of London. Series B, Containing Papers of a Biological Character107 (754). ISSN: 0950-1193. DOI: 10.1098/rspb.1931.0012.