Autor:	Sumner, Florence Anne, Ross, Roland Case, Hoffman, L. E., Edge, C. W., Huey, Laurence M., Swarth, H. S., Meadows, Don, Stoner, Emerson A., Neff, Johnson A., Howard, Hildegard, Dodson, Leigh Marian, Smith, Clarence F., Grinnell, J., Unglish, W. E., Lane, George W., Lincoln, Frederick C., Friedmann, Herbert, McCabe, Thomas T., Hanna, Wilson C., Skinner, M. P., Lofberg, Lila M., Follett, W. I.
Zdroj:	The Condor, 1933 Nov 01. 35(6), 231-245.
Databáze:	JSTOR Journals
Externí odkaz:	https://www.jstor.org/stable/1363768 Zobrazit plný text záznamu