1. Armengaud A. (1966). Démographie et sociétés, Stock, Paris.
2. Bravo, J. (1999). Fiscal Implications of Ageing Societies Regarding Public and Private Pension Systems. In Population Ageing: Challenges for Policies and Programmes in Developed and Developing Countries. Cliquet, R. and Nizamuddin (Ed).
3. Caldo, C. (1987). Geografia Umana. Palermo.
4. Creedy, J. (1998). Pensions and Population Ageing: An Economic Analysis. Cheltenham. Edward Elgar Publishing.
5. Koçi, N. (2008). Demography. Tirana.