Cita APA (7th ed.)

Lewis, D. (1984). Pencil drawing techniques. Watson-Guptill Publications.

Cita Chicago (17th ed.)

Lewis, David. Pencil Drawing Techniques. New York: Watson-Guptill Publications, 1984.

Cita MLA (9th ed.)

Lewis, David. Pencil Drawing Techniques. Watson-Guptill Publications, 1984.