Southern Ivatan dialect. Ivatan is spoken on
the islands of the Batanes province of the Philippines
relatively close to Taiwan. The palato-alveolar segments
historically derive from velars and are mostly still found
before /i/ where velars do not occur. If an underlying /i/
is posited for the remaining cases these segments can be
eliminated.

Cottle, M. and Cottle, S. 1958. The significant sounds of
Ivatan. Studies in Philippine Linguistics, by members of
the Summer Institute in Linguistics, University of Sydney.
(Oceania Linguistic Monographs, no. 3)

Heye, J. and Hidalgo, C.A. 1967. An outline of Southern
Ivatan phonology. General Linguistics 7/2: 105-120.

Hidalgo, C.A. and Hidalgo, A. 1971. A Tagmemic Grammar of
Ivatan. Linguistic Society of the Philippines, Manila.