Institute for Economic and Financial Research
KDEI, 1996
Buku Referensi
FEUI - Management Research Center (MRC), {s.a}
Majalah, Jurnal, Buletin
Artikel Jurnal
Art Address Verlag Muller GMBH , 1982
Buku Referensi
Silverstone, Paul H.
Ian Allan ltd, 1984
Buku Referensi