Dinesh Rao and  M.G.M. Khan and  Sabiha Khan,  Mathematical Programming on Multivariate Calibration Estimation in Stratified Sampling.   journal   = {International Journal of Mathematical and Computational Sciences}, [online]. World Academy of Science, Engineering and Technology.
    December 2012, vol. 72(12). 1623 - 1627
    [viewed 25 April 2024]. Available from: https://publications.waset.org/pdf/10096.