The first source is statistics of the former Federal Migration Service4 of the Russian Federation as well as data of international organizations. The second block comprises data of projects conducted by the authors as part of the Group for Migration and Ethnicity Research (GMER) of RANEPA as well as the doctoral thesis of Rocheva (2016). However, this method has limitations which are connected with missing non-users of the Internet and social networking sites and those users of social networking sites who have no identifiable attributes tying them to specific countries.