@article{GDZPPN002432994,
title = {An Isoperimetric Inequality for the Principal Eigenvalue of a Periodic-Parabolic Problem.},
journal = {Mathematische Zeitschrift},
volume = {194},
year = {1987},
pages = {121-126},
zbl = {0629.35050},
url = {http://dml.mathdoc.fr/item/GDZPPN002432994}
}
Hess, Peter. An Isoperimetric Inequality for the Principal Eigenvalue of a Periodic-Parabolic Problem.. Mathematische Zeitschrift, Tome 194 (1987) pp. 121-126. http://gdmltest.u-ga.fr/item/GDZPPN002432994/