@article{DAN_1991_320_2_a0,
     author = {M. D. Bronshtein},
     title = {Functionals containing idempotent integration and their applications to the estimation of the minimal eigenvalue of differential operators},
     journal = {Doklady Akademii Nauk},
     pages = {265--268},
     year = {1991},
     volume = {320},
     number = {2},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1991_320_2_a0/}
}