edited by Gary Hoover, Acta Campbell, Patrick J, Spain
The Reference Press, 1991
Buku Referensi
National Council of Farmer Cooperatives , 1992
Buku Teks
Prentice-Hall, 1991
Buku Referensi
Association for Investment Management and Research, 1992
Buku Teks
Brandes, Joseph
University of Pittsburgh Press, 1962
Buku Teks