Ziegler, Raymond J.
John Wiley & Sons, 1962
Buku Teks
Towle, Joseph W., author
Houghton Miffiln, 1965
Buku Teks
Dalrymple, Douglas J., author
John Wiley & Sons, 1995
Buku Teks
Reed, Edward Wilson, 1913-, author
Prentice-Hall, 1977
Buku Teks
Stokes, Charles J., author
Random House, 1969
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