Karl, C. A. (1990). Teacher observation in selected secondary schools of the Archdiocese of Chicago.
Chicago-viite (17. p.)Karl, Catherine A. Teacher Observation in Selected Secondary Schools of the Archdiocese of Chicago. 1990.
MLA-viite (8. p.)Karl, Catherine A. Teacher Observation in Selected Secondary Schools of the Archdiocese of Chicago. 1990.
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