@article{701630,
     title = {Eigenvalues of conformally invariant operators on spheres},
     booktitle = {Proceedings of the 18th Winter School "Geometry and Physics"},
     series = {GDML\_Books},
     publisher = {Circolo Matematico di Palermo},
     address = {Palermo},
     year = {1999},
     pages = {109-122},
     mrnumber = {MR1692262},
     zbl = {0958.58024},
     url = {http://dml.mathdoc.fr/item/701630}
}

Bureš, Jarolím; Souček, Vladimír. Eigenvalues of conformally invariant operators on spheres, dans Proceedings of the 18th Winter School "Geometry and Physics", GDML_Books,  (1999), pp. 109-122. http://gdmltest.u-ga.fr/item/701630/