@article{DAN_1994_335_5_a3,
     author = {S. A. Sander},
     title = {Maximum principles for elliptic problems in the finite element},
     journal = {Doklady Akademii Nauk},
     pages = {560--562},
     year = {1994},
     volume = {335},
     number = {5},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1994_335_5_a3/}
}