Devore, Wynetta
Charles E.Merrill, 1986
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Koprowska, Juliet, author
Learning, Matters, 2005
Buku Teks
Koprowska, Juliet, author
Learning Matters, 2007
Buku Teks
Dubois, Brenda, 1949-, author
Allyn and Boston, 1992
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UNSW
UNSW, 2000
Buku Teks