@article{ZVMMF_2003_43_7_a1,
     author = {I. M. Prudnikov},
     title = {Procedures for the lower convex approximations construction},
     journal = {\v{Z}urnal vy\v{c}islitelʹnoj matematiki i matemati\v{c}eskoj fiziki},
     pages = {939--950},
     publisher = {mathdoc},
     volume = {43},
     number = {7},
     year = {2003},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZVMMF_2003_43_7_a1/}
}