Yadav, S.K., Sheela Misra, S.S. Mishra, and Shankar Prasad Khanal. 2017. “Variance Estimator Using Tri-Mean and Inter Quartile Range of Auxiliary Variable”. Nepalese Journal of Statistics 1 (December):83-91. https://doi.org/10.3126/njs.v1i0.18819.