Ettedgui, Peter
Focal Press, 1999
Buku Teks
Cristiano, Giuseppe, author
Barron's, 2007
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Raynald Santika, author
2018
UI - Skripsi Membership
Halligan, Fionnuala, author
Chronicle Book, 2013
Buku Referensi
Lindgren, Ernest, author
Collier Books, 1970
Buku Teks