Jocano, F. Landa
Sulod society : a study in the kinship system and social organization of a mountain people of central panay
University of The Philippines Press, 1968
 Buku Teks SO
Dozier, Edward P.
Kalinga of Northen Luzon, Philippines / by Edward P. Dozier
Holt, Rinehart and Winston, 1967
 Buku Teks
Sinco, Vicente G.
Education in Philippine society / Vicente G. Sinco
University of Philippines , 1959
 Buku Teks
Thomas, David
Some Philippine language subgroupings : a lexicostatistical study / David Thomas and Alan Healey
[publisher not identified], 1962
 Buku Teks
Scott, William Henry
The discovery of the Igorots : Spanish contacts with the pagans of northern Luzon
New Day Publishers, 1974
 Buku Teks