Steel, P. (2011). The procrastination equation: How to stop putting things off and start getting stuff done (1st U.S. ed.). Harper.
Cita Chicago Style (17a ed.)Steel, Piers. The Procrastination Equation: How to Stop Putting Things off and Start Getting Stuff Done. 1st U.S. ed. New York: Harper, 2011.
Cita MLA (8a ed.)Steel, Piers. The Procrastination Equation: How to Stop Putting Things off and Start Getting Stuff Done. 1st U.S. ed. Harper, 2011.
Precaución: Estas citas no son 100% exactas.