Nightingale, F., Calabria, M. D., & Macrae, J. (1994). Suggestions for thought. University of Pennsylvania Press.
Cita Chicago (17th ed.)Nightingale, Florence, Michael D. Calabria, i Janet Macrae. Suggestions for Thought. Philadelphia: University of Pennsylvania Press, 1994.
Cita MLA (9th ed.)Nightingale, Florence, et al. Suggestions for Thought. University of Pennsylvania Press, 1994.
Atenció: Aquestes cites poden no estar 100% correctes.