Cita APA (7th ed.)

Robertson, I. (2001). Problem solving (1a. ed.). Psychology press.

Cita Chicago (17th ed.)

Robertson, Ian. Problem Solving. 1a. ed. Filadelfia: Psychology press, 2001.

Cita MLA (9th ed.)

Robertson, Ian. Problem Solving. 1a. ed. Psychology press, 2001.