Pareto, Vilfredo
Frederick A. Praeger, 1966
Buku Teks
edited by William R. Spriegel and Clark E. Myers
R.D. Irwin, 1953
Buku Teks
Muhammad Amin A. Samad
Ghazella, 2010
Buku Teks
José Rizal National Centennial Commission,, 1962.
Buku Teks
Hawthorne, Susan
Waterloo Press, 1985
Buku Teks