@article{AA_1990_2_5_a7,
     author = {I. Yu. Popov},
     title = {Integral equations in a~model of apertures of zero width},
     journal = {Algebra i analiz},
     pages = {189--196},
     publisher = {mathdoc},
     volume = {2},
     number = {5},
     year = {1990},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AA_1990_2_5_a7/}
}