Cita APA (7a ed.)

Robertson, J., & Hepple, N. (1962). Practical problems of the portrait painter. Darton, Longman & Todd.

Cita Chicago Style (17a ed.)

Robertson, Janet, y Norman Hepple. Practical Problems of the Portrait Painter. London: Darton, Longman & Todd, 1962.

Cita MLA (9a ed.)

Robertson, Janet, y Norman Hepple. Practical Problems of the Portrait Painter. Darton, Longman & Todd, 1962.