Não informado. (1977). Core: Collected original resources in education. Carfax Publishing.
Chicago-viite (17. p.)Não informado. Core: Collected Original Resources in Education. Oxford, Inglaterra: Carfax Publishing, 1977.
MLA-viite (8. p.)Não informado. Core: Collected Original Resources in Education. Carfax Publishing, 1977.
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