@article{CMH_1989__64_1_140143,
     author = {Alano Acona},
     title = {Sur les fonctions propres positives des vari\'et\'es de {Cartan-Hadamard.}},
     journal = {Commentarii mathematici Helvetici},
     pages = {62--83},
     publisher = {mathdoc},
     volume = {64},
     number = {1},
     year = {1989},
     zbl = {0689.53027},
     url = {http://geodesic.mathdoc.fr/item/CMH_1989__64_1_140143/}
}