Hutchinson & Co., 1958
Buku Teks
Wooldridge, S. W.
Hutchinson University Library,, 1970
Buku Teks
Getis, Arthur, author
McGraw-Hill Higher Education, 2009
Buku Teks
Unwin, Tim, author
Longman Scientific & Technical, 1992
Buku Teks
Kendall, Henry M., author
Harcourt, Brace, 1958
Buku Teks