A further three critical points theorem

Triple solutions for a Dirichlet boundary value problem involving a perturbed discrete p(k)-Laplacian operator

“…Our main tool is a local minimum theorem (Theorem 2.5) due to Ricceri (see [30,Theorem 2]), which is recalled below. We refer to the papers [22,30,32] in which Theorem 2.5 has been successfully employed for the existence of at least three solutions for two-point boundary value problems.…”

“…We refer to the papers [22,30,32] in which Theorem 2.5 has been successfully employed for the existence of at least three solutions for two-point boundary value problems. First, we give the following definition.…”

“…R is a continuous function. In this paper, based on a local minimum theorem (Theorem 2.5) due to Ricceri [30], we ensure an exact interval of the parameter , in which the problem (1) admits at least three solutions.…”

Lions-type compactness and Rubik actions on the Heisenberg group

“…These hypotheses also imply that shows that the number of solutions described below is stable with respect to small subcritical perturbations. In order to prove it, we recall a result established by Ricceri [18]. If X is a Banach space, we denote by W X the class of those functionals E : X → R having the property that if {u k } is a sequence in X converging weakly to u ∈ X and lim inf k→∞ E(u k ) ≤ E(u) then {u k } has a subsequence converging strongly to u.…”

Multiplicity Results For A Kirchho-type Doubly Eigenvalue Boundary Value Problem

“…Recently, B. Ricceri in an interesting paper [17] established the existence of at least three weak solutions to a class of Kirchhoff-type doubly eigenvalue boundary value problem using Theorem 2 of [14].…”