Smiley, Donald V.
McGraw-Hill Ryerson, 1980
Buku Teks
Silberg, Richard
Harcourt, Brace & World, 1967
Buku Teks
Burns, James McGregor
Prentice-Hall, 1972
Buku Teks
Newell, Kenneth W.
World Health Organization, 1975
Buku Teks
Miller, Wright
E.P. Dutton, 1961
Buku Teks