O`Shaughnessy, Douglas, 1950-, author
Addison-Wesley, 1987
Buku Teks
edited by James F. Kavanagh and James E. Cutting
MIT Press , 1975
Buku Teks
Horner, A. Musgrave, author
Phoenix House, 1958
Buku Teks
Hybels, Saundra, author
D. Van Nostrand, 1974
Buku Teks
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