Cita APA (7a ed.)

Tizard, B., & Harvey, D. (1977). Biology of play. Spastics International Medical [etc.].

Cita Chicago Style (17a ed.)

Tizard, Barbara, y David Harvey. Biology of Play. London [etc.]: Spastics International Medical [etc.], 1977.

Cita MLA (9a ed.)

Tizard, Barbara, y David Harvey. Biology of Play. Spastics International Medical [etc.], 1977.