@article{ZNSL_1981_108_a5,
     author = {I. A. Ibragimov and R. Z. Khas'minskii},
     title = {More on the estimation of distribution densities},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {72--88},
     year = {1981},
     volume = {108},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1981_108_a5/}
}