1. The Religiosity Cycle
http://www.gallup.com/poll/tb/religValue/20020604asp
2. Handbook of Religion and Health;Koenig,2012
3. Patterns of Religious Practice and Belief in the Last Year of Life
4. While Most Americans Believe in God, Only 36% Attend a Religious Service Once a Month or More Often, 2003
http://www.harrisinteractive.com/harris_poll/index.asp?PID=900