Citation not needed, because this is a conversation, not an encyclopedia article, and he gave a rough order of magnitude estimate which happens to be reasonably

Citation not needed, because this is a conversation, not an encyclopedia article, and he gave a rough order of magnitude estimate which happens to be reasonably correct. http://freakonomics.blogs.nytimes.com/2009/01/06/the-cost-of-fearing-strangers/ http://freakonomics.blogs.nytimes.com/2009/01/06/the-cost-of... http://childfindofamerica.org/Information.htm http://childfindofamerica.org/Information.htm