Wait, James R.
Academic Press, 1982
Buku Teks
Portocarero, Herman, 1952-
Manteau, 1992
Buku Teks
Pusat Pelayanan Jasa dan Informasi Badan Koordinasi Survei dan Pemetaan Nasional ( BAKOSURTANAL),
Majalah, Jurnal, Buletin
Smith, George Albert
Harvard University, Graduate School of Business Administration, Division of Research, 1958
Buku Teks
Erika Kothe
Springer, 2012
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