We review the results concerning types of solutions of boundary value problems for the second order nonlinear equation where is the second order linear differential form. The existence results and the multiplicity results are stated in terms of types of solutions.
"On Types of Solutions of the Second Order Nonlinear Boundary Value Problems." Abstr. Appl. Anal. 2014 (SI53) 1 - 9, 2014. https://doi.org/10.1155/2014/594931