rarum 7: bilabial trill /è/, (i) prenasalized bilabial stop with trilled release, or (ii) trilled fricated vowel as syllabic variant of labial fricative
(i) Nias (Sundic, Western Malayo-Polynesian, Austronesian), Kele, Titan, and perhaps other members of the Admiralty subgroup (Oceanic, Eastern Malayo-Polynesian, Austronesian);
(ii) Luquan Yi (Tibeto-Burman, Sino-Tibetan)
Ladefoged, Peter & Ian Maddieson (1996). The Sounds of the World’s Languages. Oxford: Blackwell. Dryer, Matthew S. (1997). Why statistical universals are better than absolute universals. Chicago Linguistic Society 33, The Panels: 123-145.