Articles in Scholarly Journals [Incomplete List]

1. Bound states for semilinear Schrödinger equations with sign-changing potential
   Calculus of Variations and Partial Differential Equations, vol. 29, no. 3, pp. 397–419, 2007
2. A Semilinear Schr?dinger Equation in the Presence of a Magnetic Field
   Archive for Rational Mechanics and Analysis, vol. 170, no. 4, pp. 277–295, 2003
3. Proceedings of the American Mathematical Society, vol. 130, no. 01, pp. 85–94, 2002
4. Communications in Contemporary Mathematics, vol. 4, no. 4, p. 763, 2002
5. Infinite Dimensional Cohomology Groups and Periodic Solutions of Asymptotically Linear Hamiltonian Systems
   Journal of Differential Equations, vol. 174, no. 2, pp. 369–391, 2001
6. Homoclinic Orbits for Asymptotically Linear Hamiltonian Systems
   Journal of Functional Analysis, vol. 187, no. 1, pp. 25–41, 2001
7. Homoclinic Solutions of Hamiltonian Systems with Symmetry
   Journal of Differential Equations, vol. 158, no. 2, pp. 291–313, 1999
8. Transactions of the American Mathematical Society, vol. 349, no. 08, pp. 3181–3235, 1997
9. SIAM Journal on Mathematical Analysis, vol. 27, no. 6, Article ID 0527088, 1996
10. On symmetric solutions of an elliptic equation with a nonlinearity involving critical Sobolev exponent
    Nonlinear Analysis, vol. 25, no. 1, pp. 41–59, 1995
11. Periodic Solutions for a Class of Nonautonomous Hamiltonian Systems
    Journal of Differential Equations, vol. 112, no. 1, pp. 226–238, 1994
12. Cohomology and Morse theory for strongly indefinite functionals
    Mathematische Zeitschrift, vol. 209, no. 1, pp. 375–418, 1992
13. A relative category and applications to critical point theory for strongly indefinite functionals
    Nonlinear Analysis, vol. 15, no. 8, pp. 725–739, 1990
14. An index theory and existence of multiple brake orbits for star-shaped Hamiltonian systems
    Mathematische Annalen, vol. 283, no. 2, pp. 241–255, 1989
15. Positive solutions of variational inequalities: A degree-theoretic approach
    Journal of Differential Equations, vol. 57, no. 1, pp. 90–111, 1985
16. On a class of variational inequalities involving gradient operators
    Journal of Mathematical Analysis and Applications, vol. 100, no. 2, pp. 486–499, 1984
17. R 3 is the Union of Disjoint Circles
    The American Mathematical Monthly, vol. 90, no. 9, p. 640, 1983
18. On the number of solutions of some semilinear elliptic boundary value problems
    Nonlinear Analysis, vol. 6, no. 1, pp. 95–116, 1982
19. Global structure of level sets of a class of nonlinear Fredholm mappings
    Nonlinear Analysis, vol. 5, no. 10, pp. 1043–1051, 1981