In his book Professor Efim Pivovar studies the phenomenon of the Russian Emigration since the second half of the 19th until the early 21st century. He analyzes specific reasons for emigration, the structure and features of the Russian diasporas in Это и многое другое вы найдете в книге The Russian Emigration: The Sociohistorical Phenomenon, its Role and Place in the Cultural and Historical Legacy (Efim I. Pivovar)