Cita APA (7th ed.)

Popper, K. [. (1999). All life is problem solving. Routledge.

Cita Chicago (17th ed.)

Popper, Karl [Raimund. All Life Is Problem Solving. London: Routledge, 1999.

Cita MLA (9th ed.)

Popper, Karl [Raimund. All Life Is Problem Solving. Routledge, 1999.