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| 2. | Coerciveness of Linear Partial Differential Operators for Functions Satisfying Zero Dirichlet-type Boundary Data, Comm. on Pure and Applied Math., V. 11, 153-174 (Doctoral Dissertation), 1958. |
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| 13. | On the Dirichlet Problem for Second Order Elliptic Equations with Coefficients Singular at the Boundary, Comm. on Pure and Applied Math., V. 13, 321-328, 1960. |
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| 18. | A Local Regularity Theorem, J. of Math. and Mechanics, V. 10, 279-287, 1961. |
| 19. | Some Unusual Boundary Value Problems, Proc. of the Symposium in Pure Math., V. IV, Part. Diff. Eq., AMS, Providence, R.I., 1961. |
| 20. | Observations Concerning a Paper by Peetre, Comm. on Pure and Applied Math., V. 14, 733-736, 1961. |
| 21. | Some Lp Estimates for Partial Differential Equations, Bulletin of the Amer. Math. Soc.V. 68, 470-474, 1962. |
| 22. | Coerciveness in Lp, Trans. of the Amer. Math. Soc., V. 107, 10-29, 1963. |
| 23. | On Lp Estimates and Regularity I, Amer. J. of Math., V. 85, 1-13, 1963. |
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| 25. | On the Dominance of Partial Differential Operators, Trans. of the Amer. Math. Soc., V. 107, 237-260, 1963. |
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| 27. | On L p Estimates and Regularity II, Mathematica Scandinavica, V. 13, 47-49, 1963. |
| 28. | On the Dominance of Partial Differential Operators II, Annali della Scuola Normale Superiore di Pisa, Pisa (3), V. 18, 255-282, 1964. |
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| 30. | On L p Estimates and Regularity III, Ricerche di Mathematica, V. 13, 192-206, 1964. |
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| 33. | Fredholm Operators and the Essential Spectrum, IMM-NYU Report 335, New York University, 1-22, 1965. |
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| 35. | On the Essential Spectrum of an Arbitrary Operator I, J. of Math. Analysis and Applications, V. 13, 205-215, 1966. |
| 36. | Interpolation Spaces by Complex Methods, Bulletin of the Amer. Math. Soc., V. 72, 526-533, 1966. |
| 37. | Nonlocal Elliptic Boundary Value Problems, Annali della Scuola Normale Superiore di Pisa, Pisa (3), V. 20, 421-441, 1966. |
| 38. | On the Invariance of the Essential Spectrum of an Arbitrary Operator II, Recirche di Matematica, V. 16, 3-26, 1967. |
| 39. | Basic Theory of Fredholm Operators, Annali della Scuole Normale Superiore di Pisa (3), V. 21, 361-380, 1967. |
| 40. | Essential Spectra of Elliptic Partial Differential Equations, Bulletin of the Amer. Math. Soc., V. 73, 567-572, 1967. |
| 41. | Complex Interpolation, Compositio Mathematica, V. 18, 117-147, 1967. |
| 42. | Intermediate Extensions in L p, Bulletin of the Amer. Math. Soc., V. 73, 979-985, 1967. |
| 43. | (with Coburn, L.A.) Joint Spectra and Interpolation of Operators, J. of Functional Analysis, V. 2, 226-237, 1968. |
| 44. | Riesz Operators and Fredholm Perturbations, Bulletin of the Amer. Math. Soc., V. 74, 1139-1144. 1968. |
| 45. | On the Invariance of the Essential Spectrum of an Arbitrary Operator III, Proc. of the Cambridge Phil. Soc., V. 64, 975-984, 1968. |
| 46. | The Spectra of Non-Elliptic Operators, Israel J. of Math., V. 6, 384-397, 1968. |
| 47. | Partial Differential Operators on L p (E n) , Bulletin of the Amer. Math. Soc., V. 75, 548-549, 1969. |
| 48. | On the Spectra of Operators on Tensor Products, J. of Functional Analysis, V. 4, 95-99, 1969. |
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| 50. | On Perturbations of Essential Spectra, J. of the London Math. Soc., V. 1, 343-347, 1969. |
| 51. | (with Lebow, A.) Norms on Quotient Spaces, Bulletin of the Amer. Math. Soc., V. 75, 1322-1325, 1969. |
| 52. | The Spectrum of Operators on Lp (En), Annali della Scuola Normale Superiore di Pisa, V. 24, 201-207, 1970. |
| 53. | The Conjugate of a Product of Operators, J. of Functional Analysis, V. 6, 26-28, 1970. |
| 54. | (with Dash, A.T.) Tensor Products and Joint Spectra, Israel J. of Math., V. 8, 191-193, 1970. |
| 55. | The Essential Spectrum of Partial Differential Operators Bounded from Below, Scripta Mathematica, V. 19, 5-6, 1973. |
| 56. | (with Berger, M.S.) Lp Embedding and Non-Linear Eigenvalue Problems for Unbounded Domains, Bulletin of the Amer. Math. Soc., V. 76, 1299-1302, 1970. |
| 57. | (with Lebow, A.) Semigroups of Operators and Measures of Noncompactness, J. of Functional Analysis, V. 7, 1-26, 1971. |
| 58. | Operators Obeying Weyl's Theorem, Scripta Mathematica, V. 19, 67-75, 1973. |
| 59. | Quantities Related to Strictly Singular Operators, Indiana Univ. Math. J., V. 21, 1061-1071, 1971. |
| 60. | Hamiltonians for Singular Potentials, Indiana Univ. Math. J., V. 22, 483-503, 1972. |
| 61. | (with Berger, M.S.) Embedding Theorems and Quasilinear Elliptic Boundary Value Problems for Unbounded Domains, Trans. of the Amer. Math. Soc., V. 172, 261-278, 1972. |
| 62. | (with Shapiro, J.) A Generalized Operational Calculus Developed from Fredholm Operator Theory, Trans. of the Amer. Math. Soc., V. 78, 741-745, 1972. |
| 63. | (with Berger, M.S.) On the Solvability of Semilinear Operator Equations and Elliptic Boundary Value Problems, Bulletin of the Amer. Math. Soc., V. 78, 741-745, 1972. |
| 64. | (with Freeman, R.S.) On the Existence, Uniqueness and Regularity of Solutions to General Elliptic Boundary Value Problems, J. of Diff. Equa., V. 15, 213-246, 1974. |
| 65. | Proper Boundary Points of the Spectrum, Osaka J. of Math., V. 12, 41-44, 1975. |
| 66. | Scattering Theory for Elliptic Operators of Arbitrary Order, Commentarii Mathematici Helvetici, V. 49, 84-113, 1974. |
| 67. | A Nonlinear Elliptic Boundary Value Problem, Annali della Scuola Normale Superiore di Pisa, V. 27, 1-10, 1973. |
| 68. | Theory of Perturbations of Partial Differential Operators, Centro Internazionale Matematico Estivo, Varenna, Spectral Analysis, Edizioni Cremonese, 187-229, 1974. |
| 69. | A Unified Approach to Scattering, J. de Mathematiques Pures et Appliques, V. 53, 373-396, 1974. |
| 70. | Essential Self-adjointness of the Schrodinger Operator with Magnetic Vector Potential, J. of Functional Analysis, V. 20, 93-101, 1975. |
| 71. | Scattering Theory for Second Order Elliptic Operators, Annali di Matematica Pura ed Applicata, V. 105, 313-331, 1975. |
| 72. | (with Snow, M.) The Fredholm Spectrum of Tensor Products, Proc. of the Royal Irish Acad., V. 75, Sec. A, 121-127, 1975. |
| 73. | Nonhomogeneous Elliptic Systems and Scattering, Tohoku Mathematical Journal, V. 27, 601-616, 1975. |
| 74. | Scattering Theory for Pseudodifferential Operators, Quarterly J. of Math., Oxford, V. 27, 111-121, 1976. |
| 75. | Scattering Theory for Elliptic Systems, J. of the Mat. Soc. of Japan, V. 28, 71-79, 1976. |
| 76. | Remarks on a Previous Paper, J. of Math. Analysis and Applications, V. 54, 138-141, 1976. |
| 77. | Discreteness of the Singular Spectrum for Schrodinger Operators , Math. Proc. of the Cambridge Phil. Soc., V. 80, pp 121-133. |
| 78. | On the Spectra of Singular Elliptic Operators, Mathematika, V. 23, 107-115, 1976. |
| 79. | The Klein-Gordon Equation and Scattering Theory, Annals of Physics, V. 101, 601-609, 1976. |
| 80. | Eigenfunction Expansions for the Schrodinger Operator, Arkiv for Matematik, V. 14, 277-287, 1976. |
| 81. | Cut-off Potentials and Forms Extensions, Letters in Math. Physics, V. 1, 265-273, 1976. |
| 82. | Differentiability of Solutions of Elliptic Problems with Respect to Parameters, Bollettino dells Unione Matematica Italino A 950, V. 13, 601-608, 1976. |
| 83. | (with Koller, H. and Weder, R.) Schrodinger Operators in the Uniform Norm, Annales de l'Institut Henri Poincare, V. 26, 303-311, 1977. |
| 84. | The Existence of Wave Operators in Scattering Theory, Bulletin of the Amer. Math. Soc., V. 83, 381-383, 1977. |
| 86. | (with Berger, M.) On the Solvability of Semilinear Gradient Operator Equations, Advances in Math., V. 25, 97-132, 1977. |
| 87. | A New Criterion for Scattering Theory, Duke Math. J., V. 44, 863-872, 1977. |
| 88. | Wave Operators for Oscillating Potentials, Letters in Math. Physics, V. 2, 127-132, 1977. |
| 89. | Another Look at Scattering Theory, International J. of Theor. Phy., V. 17, 33-41, 1978. |
| 90. | (with Shapiro, J. and Snow, M.) Solutions of the Nonlinear Problem Au = N(u) in a Banach Space, Trans. of the Amer. Math. Soc., V. 241, 69-78, 1978. |
| 91. | Scattering Theory for the Schrodinger Operator with Potentials Not of Short Range, Complex Analysis and Its Applications, Dedicated to Academician I.N. Vekua on his 70th birthday, Steklov Inst. of Math., Moscow, 1978. |
| 92. | The Invariance Principle, Commentarii Mathematici Helvetici, V. 54, 111-125, 1979. |
| 93. | Scattering in Two Hilbert Spaces, J. of the London Math. Soc., V. 19, 175-186. |
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| 95. | Two Space Scattering Theory Using the Subspace of Continuity, Letters in Math. Physics, V. 3, 521-531, 1979. |
| 96. | (with Weder, R.) Rigorous Results on the Existence of Dyon Solutions, Physical Review Letters, V. 44, 1303-1305, 1980. |
| 97. | Wave Operators for Pairs of Spaces and the Klein-Gordon Equation, Aequations Mathematicae, V. 20, 38-50, 1980. |
| 98. | The Continuous Singular Spectrum of the Schrodinger Operator, Math. Proc. of the Cambridge Phil. Soc., V. 88, 59-69. |
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| 100. | (with Weder, R.) A Theorem on th Existence of Dyon Solutions, Annals of Physics, V. 132, 292-327, 1981. |
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| 102. | (with Weder, R.A.) Dyon Solutions to Yang-Mills Equations, Quantum Mechanics in Math., Chem., and Phys., ed. K.E. Gustafson and W.P. Reinhardt, Plenum Press, New York, 1981, 359-369. |
| 103. | (with Weder, R.A.) Dyons Exist, Contributions to Analysis and Geometry, ed. D.N. Clark et al., John Hopkins Univ. Press, Baltimore, 1982, 311-319. |
| 104. | Self-Adjoint Realizations in Another Hilbert Space, Amer. J. of Math., V. 106, 43-65, 1984. |
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| 106. | Imbedding Estimates Involving New Norms and Applications, Bulletin of the American Mathematical Society, V.11, 163-166, 1984. |
| 107. | Differentiation in Abstract Spaces, Journal of Differential Equations, V.54, 1-16, 1984. |
| 108. | Derivatives of Mappings with Applications to Nonlinear Differential Equations, Transactions of the American Mathematical Society, V. 293, 53-69, 1986. |
| 109. | Semilinear Boundary Value Problems for Unbounded Domains, Michigan Mathematical Journal, V. 34, 63-76, 1987. |
| 110. | Two Space Scattering and Propagative Systems, Illinois Journal of Mathematics, V. 31, 62-88, 1987. |
| 111. | Partial Differential Equations, Encyclopedia of Physical Sciences, V. 10, 117-127, 1987. |
| 112. | Weighted Norm Estimates for Sobolev Spaces, Transactions of the American Mathematical Society, V. 304, 669-687, 1987. |
| 113. | Boundary Value Problems for Semiliner Elliptic Equations of Arbitrary Order in Unbounded Domains, Rocky Mountain Journal of Mathematics, V. 18, 519-534, 1988. |
| 114. | Potential Estimates in Orlicz Spaces, Pacific Journal of Mathematics, V. 133, 381-399, 1988. |
| 115. | Weighted Norm Inequalities for Potential Operators, Transaction of the American Mathematical Society, V. 308, 57-68, 1988. |
| 116. | Exact Estimates for Potentials, SIAM Journal on Mathematical Analysis, V. 19, 1324-1328, 1988. |
| 117. | (with R. Whitley) Best Fredholm Perturbation Theorems, Studia Mathematica, V. 90, 175-190, 1988. |
| 118. | Multiplication Operators, Canadian Journal of Mathematics, V.61, 234-249, 1989. |
| 119. | The Spectrum of the Schrodinger Operator, Transactions of the American Mathematical Society, V. 312, 115-128, 1989. |
| 120. | The Hampwile Theorem for Nonlinear Eigenvalues, Duke Mathematical Journal, V. 59, 325-335, 1989. |
| 121. | Nonlinear Elliptic Boundary Value Problems at Resonance, Nonlinear Analysis, Theory, Methods and Applications, V. 14, 889-903, 1990. |
| 122. | (with K. Tintarev) Spherical Maxima in Hilbert Space and Semilinear Elliptic Eigenvalue Problems, Differential and Integral Equations, V. 3, 889-899, 1990. |
| 123. | Nonlinear Elliptic Boundary Value Problems at Strong Resonance, American Journal of Mathematics, V. 112, 439-460, 1990. |
| 124. | (with M.S. Berger) Bifurcation from equilibria for Certain Infinite-Dimensional Dynamical Systems, Contemporary Mathematics, V. 108, 133-138, 1990. |
| 125. | Solution of Nonlinear Problems at Resonance, Indiana University Mathematics Journal, V. 39, 1061-1080, 1990. |
| 126. | (with K. Tintarev) Eigenvalues for Semilinear Boundary Value Problems, Archives of Rational Mechanics and Analysis, V. 113, 197-208, 1991. |
| 127. | The Mountain Pass Alternative, Advances in Applied Mathematics, V. 12, 91-105, 1991. |
| 128. | (with K. Tintarev) Families of First Eigenfunctions for Semilinear Elliptic Eigenvalue Problems, Duke Mathematical Journal, V. 62, 453-465, 1991. |
| 129. | The Mountain Cliff Theorem, Differential Equations and Mathematical Physics, ed. C. Bennewitz, Mathematics in Science and Engineering V. 186, Academic Press, San Diego, 263-279, 1992. |
| 130. | A Saddle Point Theorem Applied to Semilinear Boundary Value Problems, Panamerican Mathematical Journal, V. 1, Number 2, 1-25, 1991. |
| 131. | A Variation of the Mountain Pass Lemma and Applications, Journal of the London Mathematical Society, V. 44, 491-502, 1991. |
| 132. | (with K. Tintarev) Points of spherical maxima and solvability of semilinear elliptic equations. Canad. J. Math. 43 (1991), no. 4, 825-831. |
| 133. | A Bounded Mountain Pass Lemma Without the (PS) Condition and Applications, Transactions of the American Mathematical Society, V. 331, 681-703, 1992. |
| 134. | (with K. Tintarev) Pairs of Critical Points Produced by Linking Subsets with Applications to Semilinear Elliptic Problems, Bulletin de la Societe Mathematique de Belgique, V. 44, 249-261, 1992. |
| 135. | A Generalization of the Saddle Point Method with Applications, Annales Polonici Mathematici, V. 57, 269-281, 1992. |
| 136. | New saddle point theorems. Generalized functions and their applications (Varanasi, 1991), 213-219, Plenum, New York, 1993. |
| 137. | Critical Points Over Splitting Subspaces, Nonlinearity, V. 6, 417-427, 1993. |
| 138. | Splitting Subspaces and Saddle Points, Applicable Analysis, V. 49, 33-48, 1993. |
| 139. | (with K. Tintarev) Nonlinear Eigenvalues and Mountain Pass Methods, Topological Methods in Nonlinear Analysis, V. 1, 183-201, 1993. |
| 140. | Semilinear Boundary Value Problems of the Strong Resonance Type, Topological Methods in Nonlinear Analysis, V. 2, 189-202, 1993. |
| 141. | Strong Resonance Problems for Elliptic Semilinear Boundary Value Problems, Journal of Operator Theory, V. 30, 301-314, 1993. |
| 142. | Asysmptotically Linear Elliptic Boundary Value Problems, Monatshefte fur Mathematik, V. 117, 121-137, 1994. |
| 143. | The Hampwile Alternative, Communications in Applied Nonlinear Analysis, V. 1, 13-46, 1994. |
| 144. | Landesman-Lazer Resonance Problems and Saddle Point Methods, Mathematical Methods in the Applied Sciences, V. 17, 229-238, 1994. |
| 145. | The Fucik Spectrum, Indiana University Mathematics Journal, V. 43, 1139-1157, 1994. |
| 146. | Elliptic resonance problems with unequal limits at infinity. Math. Ann. 300 (1994), no. 4, 629-642. |
| 147. | (with M. S. Berger and G. Z. Sun) Infinite-dimensional singularity theory and bifurcation from equilibria for certain nonlinear evolution equations. Topological Methods in Nonlinear Analysis 4 (1994), no. 2, 341-353. |
| 148. | Bounded Resonance Problems for Semilinear Elliptic Equations, Nonlinear Analysis, Theory, Methods and Applications, V. 24, 1471-1482, 1995. |
| 149. | Superlinear Elliptic Boundary Value Problems, Manuscripta Mathematica, V. 86, 253-265, 1995. |
| 150. | (with K. Tintarev) Critical Points for Pairs of Functionals and Semilinear Elliptic Equations, in Calculus of Variations, Applications and Computations (ed. C. Bandle et al.) Pitman Research Notes in Mathematics No. 326, pp. 245-253, 1995. |
| 151. | The saddle point alternative. Amer. J. Math. 117 (1995), no. 6, 1603-1626. |
| 152. | The intrinsic mountain pass. Pacific J. Math. 171 (1995), no. 2, 529-544. |
| 153. | New techniques in critical point theory. Partial differential equations and applications, 289-294, Lecture Notes in Pure and Appl. Math., 177, Dekker, New York, 1996. |
| 154. | Critical points when there is no saddle point geometry. Topol. Methods Nonlinear Anal. 6 (1995), no. 2, 295-308. |
| 155. | New linking theorems. Rend. Sem. Mat. Univ. Padova 99 (1998), 255-269. |
| 156. | Eigenvalue problems for semilinear equations. Spectral and scattering theory (Newark, DE, 1997), 157-175, Plenum, New York, 1998. |
| 157. | Type (II) regions between curves of the Fucik spectrum. NoDEA Nonlinear Differential Equations Appl. 4 (1997), no. 4, 459-476. |
| 158. | Resonance problems which intersect many eigenvalues. Math. Nachr. 183 (1997), 201-210. |
| 159. | Critical point theory with weak-to-weak linking. Comm. Pure Appl. Math. 51(1998), no. 11-12, 1247-1254. |
| 160. | Infinite-dimensional linking. Duke Math. J. 94 (1998), no. 3, 573-595. |
| 161. | (with K. Perera) Morse index estimates in saddle point theorems without a finite-dimensional closed loop. Indiana Univ. Math. J. 47 (1998), no. 3, 1083-1095. |
| 162. | Rotationally invariant periodic solutions of semilinear wave equations. Abstr. Appl. Anal. 3 (1998), no. 1-2, 171-180. |
| 163. | (with K. Perera) Type II regions between curves of the Fucik spectrum and critical groups. Topol. Methods Nonlinear Anal. 12 (1998), no. 2, 227-243. |
| 164. | (with K. Perera) Semilinear elliptic equations having asymptotic limits at zero and infinity. Abstr. Appl. Anal. 4 (1999), no. 4, 231-242. |
| 165. | Resonance problems with respect to the Fucik spectrum. Trans. Amer. Math. Soc. 352 (2000), no. 9, 4195-4205 |
| 166. | (with K. Perera) Nontrivial solutions of elliptic semilinear equations at resonance. Manuscripta Math. 101 (2000), no. 3, 301-311. |
| 167. | (with K. Perera) A generalization of the Amann-Zehnder theorem to nonresonance problems with jumping nonlinearities. NoDEA Nonlinear Differential Equations Appl. 7 (2000), no. 4, 361-367. |
| 168. | (with K. Perera) Multiple nontrivial solutions of elliptic semilinear equations. Topol. Methods Nonlinear Anal. 16 (2000), no. 1, 1-15. |
| 169. | (with K. Perera) The Fucik spectrum and critical groups. Proc. Amer. Math. Soc. 129 (2001), no. 8, 2301-2308. |
| 170. | (with K. Perera) Applications of Morse theory to the solution of semilinear problems depending on C1 functionals. Nonlinear Anal. 45 (2001), no. 1, Ser. A: Theory Methods, 1-9. |
| 171. | (with K. Perera) Solution of nonlinear equations having asymptotic limits at zero and infinity. Calc. Var. Partial Differential Equations 12 (2001), no. 4, 3 59-369. |
| 172. | Periodic solutions of semilinear higher dimensional wave equations Chaos Solitons Fractals 12 (2001), no. 6, 1029-1034. |
| 173. | Multiple solutions for semilinear elliptic problems. Mathematika 47 (2000), no. 1-2, 307-317 (2002). |
| 174. | Principles of functional analysis. Second edition. Graduate Studies in Mathematics, 36. American Mathematical Society, Providence, RI, 2002. xxii+425 pp. ISBN: 0-8218-2895-9 |
| 175. | Some recent results in critical point theory. Panamer. Math. J. 12 (2002), no. 2, 1-19. |
| 176. | (with K. Perera) Critical groups in saddle point theorems without a finite dimensional closed loop. Math. Nachr. 243 (2002), 156-164. |
| 177. | Operator methods in quantum mechanics. Reprint of the 1981 original. Dover Publications, Inc., Mineola, NY, 2002. xxii+324 pp. ISBN: 0-486-42547-9 47N50 |
| 178. | (with W. Zou) Homoclinic orbits for Schrodinger systems. Michigan Math. J. 51 (2003), no. 1, 59-71. |
| 179. | (with K. Perera) Double resonance problems with respect to the Fucik spectrum. Indiana Univ. Math. J. 52 (2003), no. 1, 1-17. |
| 180. | (with K. Perera) Computation of critical groups in Fucik resonance problems. J. Math. Anal. Appl. 279 (2003), no. 1, 317-325. |
| 181. | (with W. Zou) On functions bounded from below. (Russian) Funktsional. Anal. i Prilozhen. 37 (2003), no. 2, 75-80, 96. |
| 182. | (with W. Zou) Weak linking theorems and Schrodinger equations with critical Sobolev exponent. ESAIM Control Optim. Calc. Var. 9 (2003), 601-619. |
| 183. | (with W. Zou) Double linking theorem and multiple solutions. J. Funct. Anal. 205 (2003), no. 1, 37-61. |
| 184. | (with Wang, Z.-Q.; Zou, W) New linking theorem and sign-changing solutions. Comm. Partial Differential Equations 29 (2004), no. 3-4, 471-488. |
| 185. | (with W. Zou) Weak linking. Nonlinear Anal. 55 (2003), no. 6, 695-706. |
| 186. | (with W. Zou) Super-linear problems. Pacific J. Math. 214 (2004), no. 1, 145-160. |
| 187. | (with W. Zou) An infinite-dimensional linking theorem and applications. J. Differential Equations 201 (2004), no. 2, 324-350. |
| 188. | (with W. Zou) The method of weak linking. Abstract and applied analysis, 323-334, World Sci. Publishing, River Edge, NJ, 2004. |
| 189. | An introduction to nonlinear analysis. Cambridge Studies in Advanced Mathematics, 95. Cambridge University Press, Cambridge, 2004. xviii+357 pp. ISBN: 0-521-84397-9. |
| 190. | Semilinear problems with bounded nonlinear term. Bound. Value Probl. 2005, no. 1, 1-8. |
| 191. | (with W. Zou) Infinitely many solutions to perturbed elliptic equations. J. Funct. Anal. 228 (2005), no. 1, 1-38. |
| 192. | Saddle point techniques. Nonlinear Anal. 63 (2005), no. 5-7, 699-711. |
| 193. | (with K. Tintarev) Linking in Hilbert space. Proc. Amer. Math. Soc. 134 (2006), no. 2, 403-410. |
| 194. | (with K. Tintarev) Finding linking sets. Int. J. Math. Math. Sci. 2006, Art. ID 24623, 13 pp. |
| 195. | Critical point theory on unbounded regions. Comm. Appl. Nonlinear Anal. 13 (2006), no. 1, 97-105. |
| 196. | Periodic non-autonomous second-order dynamical systems. J. Differential Equations 223 (2006), no. 2, 290-302. |
| 197. | (with W. Zou) Critical point theory and its applications. Springer, New York, 2006. xii+318 pp. |
| 198. | (with W. Zou) Sign-changing critical points from linking type theorems. Trans. Amer. Math. Soc. 358 (2006), no. 12, 5293-5318. |
| 199. | Periodic solutions of second-order nonautonomous dynamical systems. Bound. Value Probl. 2006, Art. ID 25104, 9 pp. |
| 200. | Sandwich pairs. Differential & difference equations and applications, 999-1007, Hindawi Publ. Corp., New York, 2006. |
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| 202. | (with K. Perera) Sandwich pairs in p-Laplacian problems. Topol. Methods Nonlinear Anal. 29 (2007), no. 1, 29-34. |
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