1. Adulyanon S, Sheiham A. (1997). In: Slade DG (ed.) Measuring Oral Health and Quality of Life. University of North Carolina, Chapel Hill.
2. Aggarwal VR, Lunt M, Zakrzewska JM, Macfarlane GJ, Macfarlane TV. (2005). Community Dent Oral Epidemiol. 33(2): 141–149.
3. Allen PF. (2003). Health Qual Life Outcomes. 1: 40–43.
4. Allen PF, Locker D. (1997). Community Dent Health. 14(3): 133–138.
5. Allen PF, Locker D. (2002). Int J Prosthodont. 15(5): 446–450.