@article{SM_1986_55_2_a11,
     author = {A. B. Merkov},
     title = {Second-order elliptic equations on graphs},
     journal = {Sbornik. Mathematics},
     pages = {493--509},
     publisher = {mathdoc},
     volume = {55},
     number = {2},
     year = {1986},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1986_55_2_a11/}
}