@article{UFA_2018_10_2_a1,
     author = {D. I. Borisov},
     title = {On spectral gaps of a {Laplacian} in a strip  with a bounded periodic perturbation},
     journal = {Ufa mathematical journal},
     pages = {14--30},
     publisher = {mathdoc},
     volume = {10},
     number = {2},
     year = {2018},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/UFA_2018_10_2_a1/}
}