J.G.E. Hopkins, Florett Robinson, Le Roy H. Appleton, James Truslow Adams, editor
Charles Scribner's Sons, 1960
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Caravan, Jill, author
Todtri Production Limited, 1996
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Friedman, Lawrence M., 1930-, author
W.W. Norton, 1984
Buku Teks
Ketchum, Richard M., author
American Heritage Publishing, 1960
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Musser, Charles, author
Macmillan Library reference USA,, 1990
Buku Referensi