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Endangered Languages of the United States ( pp. 108-130 ) . Christopher Rogers, Naomi Palosaari and Lyle Campbell (2010) · In Atlas of the World’s Languages in Danger of Disappearing edited by Christopher Moseley · UNESCO

North America ( pp. 7-41 ) . Victor Golla and Ives Goddard and Lyle Campbell and Marianne Mithun and Mauricio Mixco (2008) · In Atlas of the World's Languages edited by Chris Moseley and Ron Asher · Routledge