The research will be published in volumes with the one for Assam in both Assamese and English, while those for rest of the four states in English, he said. The volumes would be the first of its kind in the linguistic survey of Indian languages and would depict the cultural and linguistic geography of all the indigenous commuinities of the five NE states.
The articles would be written by people from diverse fields such as academics, medicine and law and will be inaugurated on September 5 in New Delhi, he said.
"Our survey has not been on linguists' perspective or to discover new languages. There are unrecorded languageswhich have been spoken for 1500 years ... They are not new languages as linguists have found them now," Devy added.
Devy said over 55 languages in Assam, 31 in Meghalaya, 28 in Manipur, 17 including its official language Nagamese in Nagaland and 10 in Tripura were endangered.
Prof Bibha Bharali of Gauhati University, who is editing the Assamese volume, said there were 55 languages accounted in the survey in the state with three associated languages of Nagamese, Sadhani and Arunachali Assamese.
Konyak was spoken by just five persons in Assam's Sibsagar district, Bharali said adding the NE states have the highest per capita language figure in the world.