References
- Bancroft , S. , Hale , J.K. and Sweet , D. 1968 . Alternative problems for non-linear functional equations . Jour. Diff. Eqs , 4 : 40 – 56 .
- Chow , S.N. and Hale , J.K. 1982 . Methods of Bifurcation Theory , New York : Springer-Verlag .
- Hale , J.K. 1969 . Ordinary Differential Equations , New York : Wiley .
- Lakshmikantham , V. and Trigiante , D. 1988 . Theory of Difference Equations , New York : Academic Press .
- LaSalle , J.P. 1976 . The stability of dynamical systems . Regional Conference Series in Appl. Math ,
- Lewis , D.C. 1956 . On the role of first integrals in the perturbation of periodic solutions . Ann. Math , 63 : 535 – 548 .
- Mansfield , A.W. and Sweet , D. 1981 . A quadratic convergence scheme for determining families of periodic solutions . J. Appl. Anal , 11 : 243 – 257 .
- Rivera , W. Center and subcenter manifolds for difference equations with a first integral
- Sweet , A. 1986 . A Newton scheme for conservatively singular systems . J. Math. Anal , 116 : 184 – 192 .
- Sweet , D. 1973 . Periodic solutions for dynamical systems possessing a first integral in the resonance case . Jour. Diff. Eqs , 14 : 171 – 183 .