Kinsella, Sophie
Jangan bilang-bilang ya... = can you keep a secret
Gramedia Pustaka Utama, 2003
 Buku Teks SO
Ruwantissa Abeyratne
Asean single aviation market and indonesia - can it keep up with the giants? / Ruwantissa Abeyratne
Faculty of Law University of Indonesia, 2014
 Artikel Jurnal
Locke, A.
The tigers of Trengganu
The Malaysian Branch of the Royal Asiatic Society, 1993
 Buku Teks
Zemke, Ron
E-Service : 24 ways to keep your customers-when the competition is just a click away
Amacom, 2000
 Buku Teks SO
Temperley, Alison
Inside knowledge: how women can thrive in professional service firms
Emerald, 2017
 eBooks