Here is another figure from a different Cole article on the Distribution of Non-Christian Groups in NW Luzon. It is helpful in understanding the first article I posted.
Attached is a PDF file of the article and the map it contains.
Ian.
Complete reference:
Distribution of the Non - Christian Tribes of Northwestern Luzon
Author(s): Fay Cooper Cole
Source: American Anthropologist, New Series, Vol. 11, No. 3 (Jul. - Sep., 1909), pp. 329-347
Published by: Wiley on behalf of the American Anthropological Association
Stable URL:
http://www.jstor.org/stable/659623
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