Shaw, Susan
John Wiley & Sons, 2009
Buku Teks SO
Susan M. Shaw and Janet Lee, editor
McGraw-Hill, 2012
Buku Teks
Barnes, Harry Elmer
Prentice-Hall, 1950
Buku Teks SO
Anderson, Maxwell
Harcout, Brace, 1926
Buku Teks SO
Reulet, Anibal Sanchez
University of Mexico Press, 1954
Buku Teks SO