@article{ARM_1990_26_4_a0,
     author = {\v{C}adek, Martin},
     title = {Pointwise transformations of linear differential equations},
     journal = {Archivum mathematicum},
     pages = {187--200},
     year = {1990},
     volume = {26},
     number = {4},
     mrnumber = {1188970},
     zbl = {0731.34008},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ARM_1990_26_4_a0/}
}