Kosakata dasar Swadesh di Kabupaten Belu, Ngada, Sumba Barat, Sumba Timur, dan Timor Tengah Utara / Tim penyusun, Buha Aritonang...[et.al]
Departemen Pendidikan dan Kebudayaan, 2002
 Buku Teks SO
Pauwels, Anne
Language maintenance and shift
NY Cambridge University Press, 2016
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Stewart, Mark Alan
GRE CAT Answers to the Real Essay Questions, 2nd edition (Arco GRE Answers to the Real Essay Questions)
Thomson, 2003
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Barr, Donald F.
Languages of Central Sulawesi checklist, preliminary classification, language maps, wordlists/ Donald F. Barr, Sharon G. Barr
Hasanuddin University, 1979
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Anderson, W.M. (Wendy M.)
English grammar essentials for dummies
Wiley Publishing Australia Pty Ltd, 2013
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