6Matthew D. Shapin, David W. ilox , Mismeasurement in the consumer price index: an evalualion, Working paper, National bureau of economic research
7Klaus Kostenbauer, Housing depreciation in the Canada CPI, Working paper, Statistic Canada,
8Robert Pool, Frank Ptacek, Randal Verbruggc, Treatment of Owcner-Occupied Housing in the CPI, Working paper, Office of Price and Living Conditions Bureau of Labor Statislics.
9World Development Indicators 2001, pp. 166 - 169, table 3: Urban Environment.