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@article{PIM_1985_N_S_38_52_a15, author = {H. Herold}, title = {Nichtlineares {Randwertproblem} 4. {Ordnung}}, journal = {Publications de l'Institut Math\'ematique}, pages = {111 }, publisher = {mathdoc}, volume = {_N_S_38}, number = {52}, year = {1985}, language = {en}, url = {http://geodesic.mathdoc.fr/item/PIM_1985_N_S_38_52_a15/} }
H. Herold. Nichtlineares Randwertproblem 4. Ordnung. Publications de l'Institut Mathématique, _N_S_38 (1985) no. 52, p. 111 . http://geodesic.mathdoc.fr/item/PIM_1985_N_S_38_52_a15/