See Shevoroshkin 1998, Shevoroshkin 2003, and Shevoroshkin 2004SHEVOROSHKIN, Vitaly V. (Fall 1998), "1998 Symposium on Nostratic at Cambridge", Mother Tongue (31), The Association for the Study of Language In Prehistory: 28–32, retrieved 2008-01-28 SHEVOROSHKIN, Vitaliy V., 2003. "Salishan and North Caucasian." Mother Tongue 8: 39–64. SHEVOROSHKIN, Vitaliy V., 2004. "Proto-Salishan and Proto-North-Caucasian Consonants: a few cognate sets." in Nostratic Centennial Conference: the Pécs Papers. ed. by. I. Hegedűs & P. Sidwell, pp. 181–191. Pécs: Lingua Franca Group.