Sorlin, Pierre
Routledge, 1991
Buku Teks
edited by Pieter J.D. Drenth, Joseph A. Sergeant, Roelf J. Takens
John Wiley & Sons, 1990
Buku Teks
Rothman, Stanley
Bobbs-Merril Company, 1970
Buku Teks
Stearns, Peter N.
Macmillan, 1967
Buku Teks
edited by Wolfgang Stroebe, Miles Hewstone
John Wiley & Sons, 1991
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