Blatt, B. (1975). Toward an understanding of people with special needs. In J. M. Kauffman, & J. S. Payne (Eds.), Mental retardation: Introduction and personal perspectives (pp. 338–427). Columbus, OH: Merrill.
2.
Hungerford, R. H. (1950). On locusts. American journal of Mental Deficiency, 54, 415–418.
3.
Rushdie, S. (1996, September 23). Reservoir frogs (or places called mama's). The New Yorker, p. 104.