@article{10_21136_CMJ_1982_101802,
     author = {Everitt, William Norrie},
     title = {On the transformation theory of ordinary second-order linear symmetric differential expressions},
     journal = {Czechoslovak Mathematical Journal},
     pages = {275--306},
     publisher = {mathdoc},
     volume = {32},
     number = {2},
     year = {1982},
     doi = {10.21136/CMJ.1982.101802},
     mrnumber = {654062},
     zbl = {0526.34026},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1982.101802/}
}