This is a description of Proto-KokBorok prepared as part of the 1987-88 Linguistic Field Methods course at University of California, Berkeley on KokBorok with some handwritten notes from Jim Matisoff. Tripura describes regional variation and provides a phoneme inventory, rhyme classes, and correspondences with Bodo.

This extremely valuable collection of texts in the Lahu language represents the language and culture in the 1960’s, a time when the heritage language and culture were still vibrant and not yet globalized, hence the title Window on a Vanished World. It is also one of the largest collections of texts in any Tibeto-Burman language. The texts are available as a book and online with the audio (originally from 1960’s magnetic tape). This is a massive achievement for all involved in the recording, conversion, and editing.