Wilhelms, F. T. (1973). Supervision in a new key. Association for Supervision and Curriculum Development.
Chicago-viite (17. p.)Wilhelms, Fred T. Supervision in a New Key. Washington: Association for Supervision and Curriculum Development, 1973.
MLA-viite (9. p.)Wilhelms, Fred T. Supervision in a New Key. Association for Supervision and Curriculum Development, 1973.
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