@article{DA_1984_24_a3,
     author = {V. I. Kostin},
     title = {Points of the extremum of a function},
     journal = {Diskretnyj analiz i issledovanie operacij},
     pages = {35--42},
     publisher = {mathdoc},
     number = {24},
     year = {1984},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DA_1984_24_a3/}
}