Cita APA (7th ed.)

Gropper, G. L., & Glasgow, Z. (1971). Criteria for the selection and use of visuals in instruction: A handbook. Educational Technology.

Cita Chicago (17th ed.)

Gropper, George L., i Zita Glasgow. Criteria for the Selection and Use of Visuals in Instruction: A Handbook. Englewood Cliffs, NJ: Educational Technology, 1971.

Cita MLA (9th ed.)

Gropper, George L., i Zita Glasgow. Criteria for the Selection and Use of Visuals in Instruction: A Handbook. Educational Technology, 1971.