@article{RSMUP_1991__86__143_0,
     author = {Spera, Mauro},
     title = {Sobolev theory for non commutative tori},
     journal = {Rendiconti del Seminario Matematico della Universit\`a di Padova},
     pages = {143--156},
     publisher = {Seminario Matematico of the University of Padua},
     volume = {86},
     year = {1991},
     mrnumber = {1154104},
     zbl = {0757.46061},
     language = {en},
     url = {http://www.numdam.org/item/RSMUP_1991__86__143_0/}
}