Aptekar, Sofya Socio-Cultural Diversity, MPI for the Study of Religious and Ethnic Diversity, Max Planck Society;
https://academic.oup.com/socpro/article/63/2/266/2461525/Gifts-Among-Strangers-The-Social-Organization-of (Publisher version)
Aptekar, S. (2016). Gifts among strangers: The social organization of freecycle giving. Social Problems, 63(2), 266-283. doi:10.1093/socpro/spw005.