Seki, Keizo
Japan Society for the Promotion of Science , 1956
Buku Teks
Matsuo, Hiroshi
The Institute of Developing Economics , 1970
Buku Teks
Cox, Clifton B.
Harvard Univ.Graduate School of Business Administration Div. of Research , 1959
Buku Teks
Robson, R.
Macmillan, 1957
Buku Teks
Hauser, William B.
Cambridge University Press, 1974
Buku Teks