Pearsall, R. (1990). Introduction to drawing. Grange Books.
Cita Chicago (17th ed.)Pearsall, Ronald. Introduction to Drawing. London: Grange Books, 1990.
Cita MLA (9th ed.)Pearsall, Ronald. Introduction to Drawing. Grange Books, 1990.
Atenció: Aquestes cites poden no estar 100% correctes.