1. Stein J (January 29, 2015) Baby, you can drive my car, and do my errands, and rent my stuff. Time. Available at http://time.com/magazine/us/3687285/february-9th-2015-vol-185-no-4-u-s/. Accessed August 9, 2017.
2. Simmel G (1955) Conflict and the Web of Group Affiliation (The Free Press, New York).
3. Lazarsfeld P Merton R (1954) Friendship as a social process: A substantive and methodological analysis. Freedom and Control in Modern Society, eds Berger M Abel T Page C (Van Nostrand, New York), pp 18–66.
4. An ecology of affiliation;McPherson;Am Socio Rev,1983
5. Birds of a Feather: Homophily in Social Networks