@article{IM2_1967_1_5_a4,
     author = {K. K. Golovkin},
     title = {The principle of locality in the theory of boundary-value problems
},
     journal = {Izvestiya. Mathematics },
     pages = {983--1010},
     publisher = {mathdoc},
     volume = {1},
     number = {5},
     year = {1967},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1967_1_5_a4/}
}