por Simmons, George Finlay, 1925- [autor] | Krantz, Steven G. (Steven George), 1951- [autor].
por Krantz, Steven G. (Steven George), 1951- [autor] | Simmons, George F. (George Finlay), 1925-. Differential equations.
por Simmons, George Finlay, 1925- [autor] | Krantz, Steven G. (Steven George), 1951- [autor] | Yescas Milanés, Jorge [traductor].