Walling, D. R. (1997). Hot buttons unraveling 10 controversial issues in education. Phi Delta Kappa Educational Foundation.
Chicago-viite (17. p.)Walling, Donovan R. Hot Buttons Unraveling 10 Controversial Issues in Education. USA: Phi Delta Kappa Educational Foundation, 1997.
MLA-viite (9. p.)Walling, Donovan R. Hot Buttons Unraveling 10 Controversial Issues in Education. Phi Delta Kappa Educational Foundation, 1997.
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