@article{MZ_1984__187_173501,
     author = {Robert Brooks},
     title = {On the {Spectrum} of {Non-Compact} {Manifolds} with {Finite} {Volume.}},
     journal = {Mathematische Zeitschrift},
     pages = {425--432},
     publisher = {mathdoc},
     volume = {187},
     year = {1984},
     zbl = {0537.58040},
     url = {http://geodesic.mathdoc.fr/item/MZ_1984__187_173501/}
}