Perum Percetakan Uang Republik Indonesia, [Date of publication not identified]
Buku Referensi
Perum Percetakan Uang Republik Indonesia, [Date of publication not identified]
Buku Referensi
Meutia Farida Hatta Swasono
Yayasan Hatta, 2007
Buku Teks SO
The Reader's Digest Association
Readers Digest Association, 1967
Buku Teks SO
Frans M. Parera
Kompas Media Nusantara, 2000
Buku Teks SO