↑Michael Martin. The Cambridge Companion to Atheism. Cambridge University Press, 2007, p. 310. ISBN 9780521842709 [Consulta: 31 maig 2012]. «Among celebrity atheists with much biographical data, we find leading psychologists and psychoanalysts. We could provide a long list, including G. Stanley Hall, John B. Watson, Carl R. Rogers...Abraham Maslow...Maslow was a second-generation atheist, and his father was a militant freethinker.»
↑Assagioli Roberto. Act of Will. New York: Synthesis Center Press, 2010. Print.