@article{EJDE_2000__2000__a185,
     author = {Weikard,  R.},
     title = {On commuting differential operators},
     journal = {Electronic journal of differential equations},
     year = {2000},
     volume = {2000},
     zbl = {0953.34073},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_2000__2000__a185/}
}