@article{GDZPPN00242116X, title = {Cubic Graphs and the First Eigenvalue of a Riemann Surface.}, journal = {Mathematische Zeitschrift}, volume = {162}, year = {1978}, pages = {87-100}, zbl = {0371.53032}, url = {http://dml.mathdoc.fr/item/GDZPPN00242116X} }
Buser, Peter. Cubic Graphs and the First Eigenvalue of a Riemann Surface.. Mathematische Zeitschrift, Tome 162 (1978) pp. 87-100. http://gdmltest.u-ga.fr/item/GDZPPN00242116X/