@article{1178230101,
author = {Takenaka, Tosiharu and Okazawa, Noboru},
title = {A Phillips-Miyadera type perturbation theorem for cosine functions of operators},
journal = {Tohoku Math. J. (2)},
volume = {30},
number = {4},
year = {1978},
pages = { 107-115},
language = {en},
url = {http://dml.mathdoc.fr/item/1178230101}
}
Takenaka, Tosiharu; Okazawa, Noboru. A Phillips-Miyadera type perturbation theorem for cosine functions of operators. Tohoku Math. J. (2), Tome 30 (1978) no. 4, pp. 107-115. http://gdmltest.u-ga.fr/item/1178230101/