Toward geology and ornithology I had meanwhile felt a growing attraction, cité par Barton Warren Evermann (1932). David Starr Jordan and his Interest in Birds, Condor, 34 (1) : 6-7. (ISSN0010-5422)
Voir à ce sujet Henry Weed Fowler (1930). David Starr Jordan and Ichthyology in the Pacific, Copeia, 1930 (4) : 108-109. (ISSN0045-8511)