Smokotin V. M. The quest for a universal language throughout human history / V. M. Smokotin, G. I. Petrova // Procedia - Social and Behavioral Sciences. 2015. Vol. 200 : The XXVI Annual International Academic Conference, Language and Culture, 27–30 October 2015. P. 107-113. URL: http://vital.lib.tsu.ru/vital/access/manager/Repository/vtls:000515948