@article{MZ_1987__194_173852,
     author = {Luchezar Stojanov and Vesselin Petkov},
     title = {Spectrum of the {Poincar\'e} {Map} for {Periodic} {Reflecting} {Rays} in {Generic} {Domains.}},
     journal = {Mathematische Zeitschrift},
     pages = {505--518},
     publisher = {mathdoc},
     volume = {194},
     year = {1987},
     zbl = {0673.58035},
     url = {http://geodesic.mathdoc.fr/item/MZ_1987__194_173852/}
}