Multiplicity results for critical $p$-Laplacian problems
  We prove the existence of $N$ distinct pairs of nontrivial solutions for critical $p$-Laplacian problems in ${\mathbb R}^N$, as well as in bounded domains. To overcome the difficulties arising from the lack of compactness, we use a recent global compactness result of Mercuri and Willem. 
Giuseppina Barletta, Pasquale Candito, Salvatore A. Marano, Kanishka   Perera
math.AP