@article{10_21136_MB_2006_134082,
     author = {Backlund, Ulf and F\"allstr\"om, Anders},
     title = {On the algebra of $A^k$-functions},
     journal = {Mathematica Bohemica},
     pages = {49--61},
     publisher = {mathdoc},
     volume = {131},
     number = {1},
     year = {2006},
     doi = {10.21136/MB.2006.134082},
     mrnumber = {2211003},
     zbl = {1109.32004},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/MB.2006.134082/}
}