@article{01455550, title = {Double and triple summation expressions obtained using perturbation theory.}, journal = {International Journal of Mathematics and Mathematical Sciences}, volume = {23}, year = {2000}, pages = {289-295}, doi = {10.1155/S0161171200000466}, zbl = {0989.81027}, language = {en}, url = {http://dml.mathdoc.fr/item/01455550} }
Mavromatis, Harry A. Double and triple summation expressions obtained using perturbation theory.. International Journal of Mathematics and Mathematical Sciences, Tome 23 (2000) pp. 289-295. doi : 10.1155/S0161171200000466. http://gdmltest.u-ga.fr/item/01455550/