共 50 条
- [28] APPROXIMATE SOLUTIONS FOR A FIRST-ORDER, NONLINEAR ORDINARY DIFFERENTIAL EQUATION AMERICAN MATHEMATICAL MONTHLY, 1961, 68 (08): : 774 - +
- [29] BOUNDED SOLUTIONS TO SYSTEMS OF ORDINARY SECOND-ORDER DIFFERENTIAL EQUATIONS DOKLADY AKADEMII NAUK SSSR, 1968, 180 (02): : 266 - &
- [30] Existence of 2π-periodic solutions for nonlinear systems of first-order ordinary differential equations at resonance Nonlinear Anal Theory Methods Appl, 1 (01):