Gittinger, J. Price, author
National Planning Association , 1965
Buku Teks
Heady, Earl O., author
Iowa State University Press, 1969
Buku Teks
Metcalf, John E., author
U.S. Department of Agriculture , 1952
Buku Teks
Taqiyyah, author
Fakultas Ekonomi dan Bisnis Universitas Indonesia, 2014
UI - Skripsi (Membership)
Muhamad Harry Kurniawan, author
Universitas Indonesia, 2016
UI - Skripsi (Membership)