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Generalized Two Stage Least Squares Estimators for a Structural Equation with Both Fixed and Random Coefficients.
Raj, Baldev, (1980)
Three-Stage Least-Squares and Generalized Double k-Class Estimators: A Mathematical Relationship.
Srivastava, V K, (1971)
On the Moments of Ordinary Least Squares and Instrumental Variables Estimators in a General Structural Equation.
Hillier, Grant H, (1984)