@article{PORMA_1977__36_2_115305,
     author = {Showalter, R.E.},
     title = {Perturbation of maximal accretive operators with right angle},
     journal = {Portugaliae mathematica},
     pages = {79--82},
     publisher = {mathdoc},
     volume = {36},
     number = {2},
     year = {1977},
     mrnumber = {0577413},
     zbl = {0431.47017},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PORMA_1977__36_2_115305/}
}