@article{DM_1989_1_3_a8,
     author = {G. I. Ivchenko and S. A. Khonov},
     title = {An asymptotic estimate for stratified finite populations},
     journal = {Diskretnaya Matematika},
     pages = {87--95},
     year = {1989},
     volume = {1},
     number = {3},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DM_1989_1_3_a8/}
}