https://staging.ncbae.edu.pk/k_course/multivariate-estimators-for-population-mean-using-multi-auxiliary-information-in-two-phase-sampling-by-ayesha-ayaz/ National College of Business administration & Economics Sun, 13 May 2018 06:44:41 +0000 hourly 1 https://wordpress.org/?v=6.9.1