1. Lave J, Wenger E. Situated learning: legitimate peripheral participation. Cambridge: Cambridge University Press; 1991.
2. IOM (Institute of Medicine).2011. The health of lesbian, gay, bisexual and transgender people: Building a foundation for better understanding. Washington, DC: The National Academies Press.
3. Gates GJ. How many people are lesbian, gay, bisexual and transgender? 2011. [8 November 2015]. Available from:
http://www.escholarship.org/uc/item/09h684x2
.
4. Gates GJ, Cooke AM. United States Census Snapshot: 2010. 2011. UCLA: The Williams Institute. Available from:
https://escholarship.org/uc/item/4j23r1rx
5. Administration on Aging. Aging statistics: Department of Health and Human Services [23 Feb 2014]. Available from:
http://www.aoa.gov/AoAroot/Aging_Statistics/
.