@article{RM_1978_33_3_a16,
     author = {A. B. Levin},
     title = {Characteristic polynomials of filtered difference modules and of~extensions of~difference fields},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {165--166},
     publisher = {mathdoc},
     volume = {33},
     number = {3},
     year = {1978},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RM_1978_33_3_a16/}
}