@article{AIHPB_1985__21_2_147_0,
     author = {Betz, Cristina and Gzyl, Henryk},
     title = {Probabilistic approach for comparing first eigenvalues},
     journal = {Annales de l'I.H.P. Probabilit\'es et statistiques},
     pages = {147--156},
     publisher = {Gauthier-Villars},
     volume = {21},
     number = {2},
     year = {1985},
     mrnumber = {798892},
     zbl = {0564.60071},
     language = {en},
     url = {http://www.numdam.org/item/AIHPB_1985__21_2_147_0/}
}