Lewis, D. (1984). Pencil drawing techniques. Watson-Guptill Publications.
Chicagoスタイル(17版)引用形式Lewis, David. Pencil Drawing Techniques. New York: Watson-Guptill Publications, 1984.
MLA(9版)引用形式Lewis, David. Pencil Drawing Techniques. Watson-Guptill Publications, 1984.
警告: この引用は必ずしも正確ではありません.