Gropper, G. L., & Glasgow, Z. (1971). Criteria for the selection and use of visuals in instruction: A handbook. Educational Technology.
Chicago-viite (17. p.)Gropper, George L., ja Zita Glasgow. Criteria for the Selection and Use of Visuals in Instruction: A Handbook. Englewood Cliffs, NJ: Educational Technology, 1971.
MLA-viite (9. p.)Gropper, George L., ja Zita Glasgow. Criteria for the Selection and Use of Visuals in Instruction: A Handbook. Educational Technology, 1971.
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