Cita APA (7th ed.)

Yoakam, G. A., & Simpson, R. G. (1949). Directed study and observation of teaching (rev. ed.). Macmillan.

Cita Chicago (17th ed.)

Yoakam, Gerald Alan, i Robert G. Simpson. Directed Study and Observation of Teaching. rev. ed. New York: Macmillan, 1949.

Cita MLA (9th ed.)

Yoakam, Gerald Alan, i Robert G. Simpson. Directed Study and Observation of Teaching. rev. ed. Macmillan, 1949.