Stamp, Laurence Dudley, 1898-1966
Penguin Books, 1960
Buku Teks
Getis, Arthur
McGraw-Hill Higher Education, 2009
Buku Teks
Unwin, Tim
Longman Scientific & Technical, 1992
Buku Teks
Kendall, Henry M.
Harcourt, Brace, 1958
Buku Teks
Getis, Arthur
McGraw-Hill, 2000
Buku Teks