@article{IM2_1970_4_6_a0,
     author = {A. V. Bitsadze},
     title = {Mikhail {Alekseevich} {Lavrent'ev} (on the seventieth anniversary of his birth)},
     journal = {Izvestiya. Mathematics},
     pages = {1203--1206},
     year = {1970},
     volume = {4},
     number = {6},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1970_4_6_a0/}
}