@article{1102983777,
author = {Mann, H. B. and Mitchell, Josephine and Schoenfeld, Lowell},
title = {A new proof of the maximum principle for doubly-harmonic functions.},
journal = {Pacific J. Math.},
volume = {27},
number = {3},
year = {1968},
pages = { 567-571},
language = {en},
url = {http://dml.mathdoc.fr/item/1102983777}
}
Mann, H. B.; Mitchell, Josephine; Schoenfeld, Lowell. A new proof of the maximum principle for doubly-harmonic functions.. Pacific J. Math., Tome 27 (1968) no. 3, pp. 567-571. http://gdmltest.u-ga.fr/item/1102983777/