Gaya APA

Lehrer, R., Schauble, L. (1998). Reasoning about Structure and Function: Children's Conception of Gears . New York: JOHN wiley & Sons.

Gaya MLA

Lehrer, Richard., Schauble, Leona. "Reasoning about Structure and Function: Children's Conception of Gears". New York: JOHN wiley & Sons, 1998. Jurnal.