@article{JEDP_1990____A6_0,
     author = {Ikawa, Mitsuru},
     title = {On poles of scattering matrices for several convex bodies},
     journal = {Journ\'ees \'equations aux d\'eriv\'ees partielles},
     eid = {6},
     pages = {1--9},
     publisher = {Ecole polytechnique},
     year = {1990},
     mrnumber = {91j:35212},
     language = {en},
     url = {http://www.numdam.org/item/JEDP_1990____A6_0/}
}