Beland, Irene L., author
Macmillan, 1981
Buku Teks
Edited by Arthur C. Beck, Jr., Ellis D. Hillmar
Reading, Massachusetts Addicon-Wesley Publishing , 1972
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Atnike Nova Sigiro, author
Fakultas Ilmu Sosial dan Ilmu Politik Universitas Indonesia, 2018
UI - Disertasi (Membership)
Harvey, Donald F., author
Prentice Hall International, 1996
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Harvey, Donald F., author
Prentice-Hall, 1992
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