editor, Maria Leach
Funk & Wagnalls Co., 1949
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Funk & Wagnalls Co., 1958
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Ferguson, John Alexander, author
National Library of Australia, 1977
Buku Referensi
Enciclopedia Britanica, 1961
Buku Referensi
Encyclopaedia Britannica, Inc. ; Funk & Wagnalls Co., 1961
Buku Referensi