Cita APA (7th ed.)

POPPER, K. R. (1979). Objective knowledge: An evolutionary approach (2nd ed.). Clarendon.

Cita Chicago (17th ed.)

POPPER, Karl R. Objective Knowledge: An Evolutionary Approach. 2nd ed. Oxford: Clarendon, 1979.

Cita MLA (9th ed.)

POPPER, Karl R. Objective Knowledge: An Evolutionary Approach. 2nd ed. Clarendon, 1979.

Atenció: Aquestes cites poden no estar 100% correctes.