@article {Bambusi20113379,
	title = {Degenerate KAM theory for partial differential equations},
	journal = {Journal of Differential Equations},
	volume = {250},
	number = {8},
	year = {2011},
	note = {cited By (since 1996)3},
	pages = {3379-3397},
	abstract = {This paper deals with degenerate KAM theory for lower dimensional elliptic tori of infinite dimensional Hamiltonian systems, depending on one parameter only. We assume that the linear frequencies are analytic functions of the parameter, satisfy a weak non-degeneracy condition of R{\"u}ssmann type and an asymptotic behavior. An application to nonlinear wave equations is given. {\textcopyright} 2010 Elsevier Inc.},
	issn = {00220396},
	doi = {10.1016/j.jde.2010.11.002},
	author = {Dario Bambusi and Massimiliano Berti and Elena Magistrelli}
}
