Cita APA (7th ed.)

Perkins, E., Baird, D., Capie, A. C. M., & Taylor, P. D. (1980). Helping the retarded: A systematic behavioural approach (2nd ed.). British Institute of Mental Handicap.

Cita Chicago (17th ed.)

Perkins, E.A, David Baird, A. C. M. Capie, i P. D. Taylor. Helping the Retarded: A Systematic Behavioural Approach. 2nd ed. Kidderminster, Worcs: British Institute of Mental Handicap, 1980.

Cita MLA (9th ed.)

Perkins, E.A, et al. Helping the Retarded: A Systematic Behavioural Approach. 2nd ed. British Institute of Mental Handicap, 1980.