Yadav, Rohini, Lakshmi N. Upadhyaya, Housila P. Singh, and S. Chatterjee. 2013. “A Chain Ratio Exponential Type Estimator in Two-Phase Sampling Using Auxiliary Information”. Statistica 73 (2):221-34. https://doi.org/10.6092/issn.1973-2201/4133.