@article{10_14708_cm_v14i1_5686,
     author = {Z. Ciesielski},
     title = {On the spectrum of the {Laplace} operator},
     journal = {Commentationes Mathematicae},
     pages = { 41--50},
     year = {1970},
     volume = {14},
     number = {1},
     doi = {10.14708/cm.v14i1.5686},
     language = {pl},
     url = {http://geodesic.mathdoc.fr/articles/10.14708/cm.v14i1.5686/}
}