Megan Richardson, author
Cambridge University Press, 2017
eBooks
Suara Bangawan, [Year of publication not identified]
Buku Teks
Wiley-Blackwell, 2010
eBooks
Ronald, D. A. B., author
an imprint of Bloomsbury Publishing Plc, 2015
Buku Teks
Ashanti Widyana, author
2016
UI - Skripsi (Membership)