Karl, C. A. (1990). Teacher observation in selected secondary schools of the Archdiocese of Chicago.
Παραπομπή σε μορφή Chicago (17η εκδ.)Karl, Catherine A. Teacher Observation in Selected Secondary Schools of the Archdiocese of Chicago. 1990.
Παραπομπή σε μορφή MLA (8th εκδ.)Karl, Catherine A. Teacher Observation in Selected Secondary Schools of the Archdiocese of Chicago. 1990.
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