Kreutzmann, Hermann. 2005. 'Linguistic Diversity in Space and Time: a Survey in the Eastern Hindukush and Karakoram.' Himalayan Linguistics Journal 4. 1-24.

Comparatively small populations inhabit the Hindukush-Himalayan mountain arc. Within high mountain research these areas have been termed as regions of refuge characterized by isolation, remoteness and limited to non-existent exchange relations. This study follows a different approach based on an historical reconstruction of population processes. Empirical evidence is presented from fieldwork in the Eastern Hindukush and Karakoram. The existence of isolated linguistic domains superficially suggests conservation through remoteness. Nevertheless lowland-highland migration and intra-montane mobility seem to be the driving force of population differentiation. These forces support an enhanced linguistic diversification. Increased accessibility, growing mobility and improved exchange relations did not reduce the persistence of these factors so far.