Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{MZ_1956__65_169600, author = {D.L. Dolph and R.K. Ritt}, title = {The {Schwinger} variational principles for one-dimensional quantum scattering.}, journal = {Mathematische Zeitschrift}, pages = {309--326}, publisher = {mathdoc}, volume = {65}, year = {1956}, zbl = {0070.44405}, url = {http://geodesic.mathdoc.fr/item/MZ_1956__65_169600/} }
D.L. Dolph; R.K. Ritt. The Schwinger variational principles for one-dimensional quantum scattering.. Mathematische Zeitschrift, Tome 65 (1956), pp. 309-326. http://geodesic.mathdoc.fr/item/MZ_1956__65_169600/