APA (7th ed.) Citation

Larkin, J. (1981). Cognition of learning physics. American Journal of Physics, 49, 534.

Chicago Style (17th ed.) Citation

Larkin, J. "Cognition of Learning Physics." American Journal of Physics 49 (1981): 534.

MLA (9th ed.) Citation

Larkin, J. "Cognition of Learning Physics." American Journal of Physics, vol. 49, 1981, p. 534.