Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{MOMA_1962__66_177157, author = {A. Erd\'elyi}, title = {An {Example} in {Singular} {Perturbations.}}, journal = {Monatshefte f\"ur Mathematik}, pages = {123--127}, publisher = {mathdoc}, volume = {66}, year = {1962}, zbl = {0201.14401}, url = {http://geodesic.mathdoc.fr/item/MOMA_1962__66_177157/} }
A. Erdélyi. An Example in Singular Perturbations.. Monatshefte für Mathematik, Tome 66 (1962), pp. 123-127. http://geodesic.mathdoc.fr/item/MOMA_1962__66_177157/