[Migration and migratory behavior]

"The article considers theoretical and methodological peculiarities in studying...migration and migratory behaviour.... The author makes use of the information obtained from [censuses and current demographic statistics for Bulgaria as well as] information from representative sociological studies.... The author uses [a] mathematical model in modelling migration and migratory behaviour, emphasizing the need for a profound sociological study of the main stimuli which influence the migratory processes and the extent of their impact on individuals." (SUMMARY IN ENG AND RUS)