Kreveld, D. v. (1970). Structure and outcomes of study groups: A method of determining several properties of group structure and some relationships observed with group outcomes. Van Gorcum.
Trích dẫn kiểu Chicago (xuất bản lần thứ 7)Kreveld, David van. Structure and Outcomes of Study Groups: A Method of Determining Several Properties of Group Structure and Some Relationships Observed with Group Outcomes. Assen: Van Gorcum, 1970.
Trích dẫn kiểu MLA (xuất bản lần thứ 8)Kreveld, David van. Structure and Outcomes of Study Groups: A Method of Determining Several Properties of Group Structure and Some Relationships Observed with Group Outcomes. Van Gorcum, 1970.
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