University League for Social Reform; edited by Peter Russell
McGraw-Hill, 1966
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Creighton, Donald, author
Macmillan, 1959
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Creighton, Donald, author
Macmillan, 1981
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Birdsall, Stephen S., author
John Wiley & Sons, 1992
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Morton, Desmond, author
Hurtiga, [s.a.]
Buku Teks