Left to right: Psychologists Norman R. F. (Raymond Frederick) Maier (1900-1977), Nathan M. Glaser (d. 2011), and Barbara Jean Sherburne (Stewart) (b. 1914). Maier is holding one of the rats used in their experiments; Sherburne is holding her cat "Peter" (who lived in the laboratory). Maier worked at University of Michigan from 1931-1977, so this photograph was probably taken in the Michigan laboratory