Miller McPherson, Lynn Smith-Lovin, and Matthew E. Brashears, «Social Isolation in America: Changes in Core Discussion Networks over Two Decades», American Sociological Review 71, no. 3 (2006): 353–375; см. также классический труд на эту тему Claude S. Fischer, To Dwell Among Friends: Personal Networks in Town and City (Chicago: University of Chicago Press, 1982).
