Endro Utomo Notodisuryo
Jakarta: Energy conservation workshop, 1996,
Buku Referensi
Pohan, Hazairin
Jurnal Kajian Wilayah Eropa, 2008
Artikel Jurnal
Organisation for Economic Co-operation and Development
OECD, 1974
Buku Teks
edited by Thomas Easton
McGraw-Hill, 2012
Buku Teks
Artikel Jurnal