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            | Abstract |  
            | We consider the fourth-order problem  |  | 
   where 
 and 
 are
 spatial distributions of external potentials. We study the concentration phenomena of the
 solutions as 
 using variational methods.
  |  
          
            | Keywords
                nonlinear biharmonic Schrödinger equations, standing waves,
                critical point theory
               |  
          
            | Mathematical Subject Classification 2010
                Primary: 35J10, 35Q40, 47J30
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            | Milestones
                Received: 31 July 2015
               
                Revised: 20 December 2016
               
                Accepted: 20 December 2016
               
                Published: 19 June 2017
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