@article{CM_1975__30_3_293_0,
     author = {Lewis, D. R.},
     title = {An isomorphic characterization of the {Schmidt} class},
     journal = {Compositio Mathematica},
     pages = {293--297},
     publisher = {Noordhoff International Publishing},
     volume = {30},
     number = {3},
     year = {1975},
     mrnumber = {374968},
     zbl = {0321.46017},
     language = {en},
     url = {http://www.numdam.org/item/CM_1975__30_3_293_0/}
}