WASET
    Mahmoud I. Syam and  Kamarulzaman Ibrahim and  Amer I. Al-Omari,  Estimating the Population Mean by Using Stratified Double Extreme Ranked Set Sample.   journal   = {International Journal of Mathematical and Computational Sciences}, [online]. World Academy of Science, Engineering and Technology.
    March 2015, vol. 100(4). 228 - 234
    [viewed 08 May 2024]. Available from: https://publications.waset.org/pdf/10001069.