@article{1102995087,
author = {Kegley, J. Colby},
title = {Convexity with respect to Euler-Lagrange differential operators.},
journal = {Pacific J. Math.},
volume = {19},
number = {3},
year = {1966},
pages = { 87-111},
language = {en},
url = {http://dml.mathdoc.fr/item/1102995087}
}
Kegley, J. Colby. Convexity with respect to Euler-Lagrange differential operators.. Pacific J. Math., Tome 19 (1966) no. 3, pp. 87-111. http://gdmltest.u-ga.fr/item/1102995087/