@incollection{hunter:1981:tpe,
    author = {Hunter, C.},
     title = {Two Parametric Eigenvalue Problems of Differential Equations},
 booktitle = {Spectral Theory of Differential Operators (Birmingham, AL,
              1981)},
    series = {North-Holland Math. Stud.},
    volume = {55},
     pages = {233–241},
 publisher = {North-Holland},
   address = {Amsterdam},
      year = {1981},
   mrclass = {34B30 (34E20)},
  mrnumber = {MR0640892 (83a:34030)},
mrreviewer = {H. Hochstadt},
     zblno = {0489.34017}}