@incollection{JEDP_1992____A6_0,
     author = {Vodev, Georgi},
     title = {Sharp bounds for the number of the scattering poles},
     booktitle = {},
     series = {Journ\'ees \'equations aux d\'eriv\'ees partielles},
     eid = {6},
     pages = {1--5},
     publisher = {Ecole polytechnique},
     year = {1992},
     zbl = {0771.35039},
     language = {en},
     url = {http://www.numdam.org/item/JEDP_1992____A6_0/}
}