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Scott, Foresman and Company, 1967
Koleksi Publik
Lester, James D.
Scott, Foresman and Company, 1987
Buku Teks
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Scott, Foresman and Company, 1971
Buku Teks
Laster, James D
Scott, Foresman and Company, 1984
Buku Teks
Biech, Elaine
ASTD press, 2009
Buku Teks