5Duncan, Gregory M. , 1983, "Sample Selectivity as a Proxy Variable Problem On the Use and Misuse of Gausslan Selectivity Corrections," In New Approaches to Lahor Unions, edited by Joseph Reid. Research in Labor Economies, suppl. 2, 333-45.
6Duncan, Gregory M. and Duane E. Leigh, 1985, "The Endogeneity of Union Status: An Empirleal Test," Journal of Labor Economics, Vol. 3, No. 3, 385-402.
7Erbsland, M. and V. Ulrich, 1995, "Health, ftealth Care, and the Environment: Econometric Evidence from German Micro Data," Health Economics 4. 169-182.
8Goldberger, Arthur S., 1983, "Abnormal Selection Bias," in Samuel Karlin, Takeshi Amemiya, and Leo A. Goodman (ed.) Studies in Econometrics, Time Series, and Multivariate Statistics, New York. Academic Press, 67-84.
9Gorgens, Tve, Xin Meng and Rhema Vaithianathar, 2003, "Selection and Stunting Effects of Famine: A Case Study of the Great Chinese Famine. ".
10Grossman, M. , 1972, "On the Concept of Health Capital and the Demand for Health," Journal of Political Economy 80, 223-255.
