Quasi-Exactly Solvable Potentials with Three Known Eigenstates
  We propose a new SUSY method for construction of the quasi-exactly solvable (QES) potentials with three known eigenstates. New QES potentials and corresponding energy levels and wave functions of the ground state and two lowest excited state are obtained. The proposed scheme allows also to construct families of exactly solvable non-singular potentials which are SUSY partners of the well-known ones. 
T. V. Kuliy and V. M. Tkachuk