Kellough, R. D., Kellough, N. G., & Kim, E. C. (1999). Secondary school teaching: A guide to methods and resources : planning for competence (rev. ed.). Merrill.
Chicago-viite (17. p.)Kellough, Richard D., Noreen G. Kellough, ja Eugene C. Kim. Secondary School Teaching: A Guide to Methods and Resources : Planning for Competence. rev. ed. Upper Saddle River, N.J: Merrill, 1999.
MLA-viite (9. p.)Kellough, Richard D., et al. Secondary School Teaching: A Guide to Methods and Resources : Planning for Competence. rev. ed. Merrill, 1999.
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