Kaplan Langman, Ida (1964). A selected guide to the literature on the flowering plants of Mexico. Philadelphia: University of Pennsylvania Press. OCLC4817617.
Todd, Angela L. (Spring 2004). "Ida Kaplan Langman (1904–1991)". Bulletin of the Hunt Institute for Botanical Documentation. 16 (1): 8–9, 12. ISSN0192-3641.