@article{04159449,
title = {Remarks on quadratic equations in Banach space.},
journal = {International Journal of Mathematics and Mathematical Sciences},
volume = {13},
year = {1990},
pages = {611-616},
doi = {10.1155/S0161171290000850},
zbl = {0706.47003},
language = {en},
url = {http://dml.mathdoc.fr/item/04159449}
}
Argyros, Ioannis K. Remarks on quadratic equations in Banach space.. International Journal of Mathematics and Mathematical Sciences, Tome 13 (1990) pp. 611-616. doi : 10.1155/S0161171290000850. http://gdmltest.u-ga.fr/item/04159449/