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Robust Regression for Clustered Data with Application to Binary Responses
Preisser, John S., (1999)
Sample Size Considerations for GEE Analyses of Three-Level Cluster Randomized Trials
Teerenstra, Steven, (2010)
A Comparison of Two Bias-Corrected Covariance Estimators for Generalized Estimating Equations
Lu, Bing, (2007)