On some variational algebraic problems
  In this paper by exploiting critical point theory, the existence of two distinct nontrivial solutions for a nonlinear algebraic system with a parameter is established. Our goal is achieved by requiring an appropriate behavior of the nonlinear term $f$ at zero and at infinity. Some applications to difference equations are also presented. 
Giovanni Molica Bisci and Du\v{s}an D. Repov\v{s}
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