Shafer, C. (1985). Excellence in teaching with the seven laws: A contemporary abridgment of Gregory's seven laws of teaching. Baker.
Chicago-viite (17. p.)Shafer, Carl. Excellence in Teaching with the Seven Laws: A Contemporary Abridgment of Gregory's Seven Laws of Teaching. Grand Rapids: Baker, 1985.
MLA-viite (9. p.)Shafer, Carl. Excellence in Teaching with the Seven Laws: A Contemporary Abridgment of Gregory's Seven Laws of Teaching. Baker, 1985.
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