@article{10_21136_CMJ_1990_102378,
     author = {Chrastina, Jan},
     title = {From elementary algebra to {B\"acklund} transformations},
     journal = {Czechoslovak Mathematical Journal},
     pages = {239--257},
     publisher = {mathdoc},
     volume = {40},
     number = {2},
     year = {1990},
     doi = {10.21136/CMJ.1990.102378},
     mrnumber = {1046292},
     zbl = {0726.58041},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1990.102378/}
}