@article{1077465594,
author = {Shapiro, Victor L.},
title = {Generalized Laplacians of the second kind and double
trigonometric series},
journal = {Duke Math. J.},
volume = {21},
number = {1},
year = {1954},
pages = { 173-178},
language = {en},
url = {http://dml.mathdoc.fr/item/1077465594}
}
Shapiro, Victor L. Generalized Laplacians of the second kind and double
trigonometric series. Duke Math. J., Tome 21 (1954) no. 1, pp. 173-178. http://gdmltest.u-ga.fr/item/1077465594/