1. Index Numbers in Theory and Practice;Allen,1975
2. Anessi, E.P., 1997. The effect of user charges on the utilization of prescription medicines in the Italian National Health Service. Unpublished doctoral dissertation, The Wharton School, University of Pennsylvania, Philadelphia.
3. Twenty Years of Pharmaceutical Research Results throughout the World (1975–1994);Barral,1995
4. Auditing the producer price index: micro evidence from prescription pharmaceutical preparations;Berndt;Journal of Economics and Business Statistics,1993
5. The Changing Environment for US Pharmaceuticals,1993