"The Ubo are a Manobo sub-tribe who inhabit the more isolated mountains of Southwest Cotabato in the area known as Datal Tabayong, as well as, more southerly Davao del Sur. As of last count, they numbered close to 17,000 (OSCC, 1987); a follow up on their numbers in subsequent years has proved difficult." - http://www.ethnicgroupsphilippines.com/people/ethnic-groups-in-the-philippines/manobo-obo/, 22.12.2018
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