PRAYAS SHARMA; RAJESH SINGH. Improved Ratio Type Estimator Using Two Auxiliary Variables under Second Order Approximation. Mathematical Journal of Interdisciplinary Sciences, [S. l.], v. 2, n. 2, p. 179–190, 2014. DOI: 10.15415/mjis.2014.22014. Disponível em: https://mjis.chitkara.edu.in/index.php/mjis/article/view/129. Acesso em: 30 apr. 2024.