Base, Buddhadeva
Orient Longmans , 1948
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edited by T. Lynn Smith and Alexander Marchant
Dryden Press, 1951
Buku Teks SO
Kania Rianti
Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2014
UI - Skripsi Membership
Hailey
Macmillan, 1950
Buku Teks SO
Stuart, Peter C.
Far horizon books, 1989
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