Autor:	Jewett, Stanley G., Lofberg, Lila M., Mailliard, Joseph, Moffitt, James, Sumner, F. B., Wetmore, Alexander, Smith, Austin, Compton, Lawrence V., Wilson, Irene, Campbell, Berry, Bailey, Alfred M., Niedrach, R. J., Neff, Johnson A., Stoner, Emerson A., Hanna, Wilson C., Grinnell, J.
Zdroj:	The Condor, 1931 Nov 01. 33(6), 245-256.
Databáze:	JSTOR Journals
Externí odkaz:	https://www.jstor.org/stable/1363695 Zobrazit plný text záznamu