@misc
{TN_libero_mab2,
author = {
Nambu, Takao
},
title = {
Degenerate self-adjoint perturbation in Hilbert space
},
publisher = {Project Euclid},
isbn = {0386-2194},
keywords = {
General Mathematics
},
year = {1987},
url = {
http://slubdd.de/katalog?TN_libero_mab2
}
}