1. Use of auxiliary information in estimating the finite population variance;Das;Sankhya,1978
2. A class of estimators using auxiliary information for estimating finite population variance;Srivstava;Sankhya, C,1980
3. Estimation of population variance using ratio and product methods of estimation;Singh;Biometika,1983
4. Ratio estimators for the population variance in simple and stratified random sampling;Kadilar;Appl. Math. Comput.,2006
5. On improvement in variance estimation;Shabbir;Commun. Stat. - Theor. Method.,2007