Drake, Ellen, author
Elsevier Saunder, 2012
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World Book, 1992
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Ingo-Eric M.
London : k.C. Saur Munchen, 1981,
Buku Referensi
edited by Clarence L. Barnhart and Robert K. Barnhart
World Book-Childcraft International, 1978
Buku Referensi
The Commercial Press, 1937
Buku Teks