1. Becer, E. (2001). İletişim ve grafik tasarım. (3rd ed.). (pp. 33). Ankara: Dost Kitabevi Yayınları.
2. Chaet, B. (1983). The art of drawing. (3rd ed.). Florida: Rinehart and Winston Inc.
3. Edwards, B. (1986). Drawing on the artist within. (pp. 50,126-131). New York: Simon & Schuster, Inc.
4. Enstice, W., & Peters, M. (1990). Drawing, space, form, expression. (pp. 64-78). New Jersey: Prentice-Hall, Inc.
5. Fleming, W. (1995). Arts and ideas. Orlando: Harcourt Brace Company.