Wertheim, Jane
Usborne Publishing, 1986
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editor in chief, Charles A. Ford
Encyclopedia Britannica Educational Corporation, 1969
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Burden, Ernest E., 1934-, author
McGraw-Hill, 2012
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Maddex, Robert L., author
Routledge, 1996
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Sattler, Helen Roney
Lothrop, Lee & Shepard Books, 1983
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