Flanagan, Robert J.
Scott, Foresman, 1984
Buku Teks SO
Bryce, Murray D.
McGraw-Hill, 1960
Buku Teks
Mills, Daniel Quinn
McGraw-Hill, 1994
Buku Teks SO
National Academy of Sciences-National Academy of Engineering , 1973
Buku Teks SO
Lovejoy, Laurence C.
Aleander Hamilton Institute, 1962
Buku Teks SO