. ▁ ▁Dia lect s ▁are ▁K ash ib o ▁( K as chin õ ), ▁Rub o / Is un bo , ▁K ak ata ib o , ▁and ▁N ok aman , ▁which ▁until ▁recently ▁had ▁been ▁thought ▁to ▁be ▁ext inct . ▁ ▁Ph on ology ▁ ▁Cons on ants ▁▁ ▁The ▁con son ant ▁invent ory ▁includes ▁both ▁a ▁bil ab ial ▁approxim ant , ▁realized ▁as ▁[ β <0xCC> <0x9E> ], ▁and ▁a ▁lab ial - vel ar ▁approxim ant ▁/ w /. ▁ ▁V ow els ▁▁ ▁Back ▁v ow els ▁/ o / ▁and ▁/ u / ▁are ▁ph on et ically ▁realized ▁as ▁less ▁rounded ; ▁[ o <0xCC> <0x9C> ], ▁[ u <0xCC> <0x9C> ]. ▁ ▁Statistics ▁The ▁language ▁is ▁official ▁along ▁the ▁Agu ay t ía , ▁San ▁Ale j andro , ▁and ▁S ú ng aro ▁rivers ▁in ▁Perú ▁where ▁it ▁is ▁most ▁widely ▁spoken . ▁It ▁is ▁used ▁in ▁schools ▁until ▁third ▁grade . ▁There ▁are ▁not ▁many ▁mon ol ing uals , ▁although ▁some ▁women ▁over ▁the ▁age ▁of ▁fifty ▁are . ▁ ▁There ▁is ▁five ▁to ▁ten ▁percent ▁liter acy ▁compared ▁to ▁fifteen ▁to ▁twenty - five ▁percent ▁liter acy ▁in ▁Spanish ▁as ▁a ▁second ▁language . ▁A ▁C ash ib o - C ac ata ib o ▁dictionary ▁has ▁been ▁compiled , ▁and ▁there ▁is ▁a ▁body ▁of ▁literature , ▁especially ▁poetry . ▁ ▁References ▁▁ ▁Campbell , ▁L yle . ▁( 1 9 9 7 ). ▁American