Collis, M. (1974). Tackling problems part 1: A unit for teachers. Macdonald Educational.
Chicago Style aipamenaCollis, Margaret. Tackling Problems Part 1: A Unit for Teachers. London: Macdonald Educational, 1974.
MLA aipamenaCollis, Margaret. Tackling Problems Part 1: A Unit for Teachers. Macdonald Educational, 1974.
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