Biles, Daniel C.López Pouso, Rodrigo2020-06-062020-06-062009Biles, D., López Pouso, R. First-Order Singular and Discontinuous Differential Equations. Bound Value Probl 2009, 507671 (2009). https://doi.org/10.1155/2009/5076711687-2762http://hdl.handle.net/10347/22855We use subfunctions and superfunctions to derive sufficient conditions for the existence of extremal solutions to initial value problems for ordinary differential equations with discontinuous and singular nonlinearities.engCopyright © 2009 D. C. Biles and R. Lopez Pouso. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly citedhttp://creativecommons.org/licenses/by/2.0/Weak SolutionExtremal SolutionCountable FamilyGreat SolutionNull Measurejournal article10.1155/2009/5076711687-2770open access