Voluntary, Nonprofit, and Religious Entities and Activities from Colonial Times to the Present.

Hall, Peter Dobkin, and Colin B. Burke. "Voluntary, Nonprofit, and Religious Entities and Activities from Colonial Times to the Present." Historical Statistics of the United States - Millennial Edition. Ed. Susan B. Carter, Scott Sigmund Gartner, Michael R. Haines, et al. Cambridge University Press, 2006.