@article{olver:1975:sol,
    author = {Olver, F. W. J.},
     title = {\NOOP{A}Second-order linear differential equations with two turning
              points},
   journal = {Philos. Trans. Roy. Soc. London Ser. A},
    volume = {278},
      year = {1975},
     pages = {137–174},
   mrclass = {34E20},
  mrnumber = {MR0369844 (51 \#6073)},
mrreviewer = {P. F. Hsieh},
     links = {\URL[FullText]{http://links.jstor.org/sici?sici=0080-4614%2819750320%29278%3A1279%3C137%3ASLDEWT%3E2.0.CO%3B2-N}},
     zblno = {0301.34072}}