@article{MZ_1978__162_172717,
     author = {Peter Buser},
     title = {Cubic {Graphs} and the {First} {Eigenvalue} of a {Riemann} {Surface.}},
     journal = {Mathematische Zeitschrift},
     pages = {87--100},
     publisher = {mathdoc},
     volume = {162},
     year = {1978},
     zbl = {0371.53032},
     url = {http://geodesic.mathdoc.fr/item/MZ_1978__162_172717/}
}