Cita APA (7th ed.)

International Congress of Psychology Sydney, N.S.W, & Keats, J. A. (1989). Mathematical and theoretical systems. North-Holland.

Cita Chicago (17th ed.)

International Congress of Psychology Sydney, N.S.W, i J. A. Keats. Mathematical and Theoretical Systems. Amsterdam: North-Holland, 1989.

Cita MLA (9th ed.)

International Congress of Psychology Sydney, N.S.W, i J. A. Keats. Mathematical and Theoretical Systems. North-Holland, 1989.