Proto-Northwest Caucasian, or How to Crack a Very Hard Nut

(1989, a) Proto-Northwest Caucasian, or How to Crack a Very Hard Nut, in Howard I. Aronson (ed.), The Non-Slavic Languages of the USSR, Linguistic Studies, University of Chicago:  Chicago Linguistic Society, pp. 20-55.  [reprinted in The Journal of Indo-European Studies 22.1-2: 1-35, 1994]