King, Martin Luther
Harper & Row Publhers, 1968
Buku Teks SO
Hardy, Thomas, 1840-1928
Macmillan, 1952
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Buckley-Archer, Linda
Mizan , 2009
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Labarge, Margaret Wade
Beason Press, 1986
Buku Teks SO
Teddy Nurcahyawan
1999
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