@article{01534272, title = {Harmonic sum and duality.}, journal = {Journal of Convex Analysis}, volume = {7}, year = {2000}, pages = {95-113}, zbl = {0964.49020}, language = {en}, url = {http://dml.mathdoc.fr/item/01534272} }
Penot, Jean-Paul; Zălinescu, Constantin. Harmonic sum and duality.. Journal of Convex Analysis, Tome 7 (2000) pp. 95-113. http://gdmltest.u-ga.fr/item/01534272/