@article{01685995,
title = {Sufficient conditions for functions to form Riesz bases in },
journal = {Electronic Journal of Differential Equations (EJDE) [electronic only]},
volume = {2001},
year = {2001},
zbl = {1009.34077},
language = {en},
url = {http://dml.mathdoc.fr/item/01685995}
}
Zhidkov, Peter E. Sufficient conditions for functions to form Riesz bases in . Electronic Journal of Differential Equations (EJDE) [electronic only], Tome 2001 (2001) . http://gdmltest.u-ga.fr/item/01685995/