The dual eigenvalue problems for $p$-Laplacian
  In this paper, we find the minimizer of the eigenvalue gap for the single-well potential problem and the eigenvalue ratio for the single-barrier density problem and symmetric single-well (single-barrier)density problem for $p$-Laplacian. This extends the results of the classical Sturm-Liouville problem. 
Y.H. Cheng, Wei-Cheng Lian and Wei-Chuan Wang
math.CA