Mitchell, Wesley C., author
National Bureau of Economic Researsch, 1930
Buku Teks
Richard V.Clemence
W.W. Norton and Company,Inc., 1953
Buku Teks
edited by Willi Semmler
Kluwer, 1994
Buku Teks
Holden, K., author
Cambridge University Press, 1990
Buku Teks
edited by Kenneth D. Lawrence, Ronald K. Klimberg
Emerald, 2016
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