@article{10_4064_cm139_1_6,
     author = {Tomasz Brzezi\'nski},
     title = {Differential smoothness of affine {Hopf} algebras of {Gelfand{\textendash}Kirillov} dimension two},
     journal = {Colloquium Mathematicum},
     pages = {111--119},
     publisher = {mathdoc},
     volume = {139},
     number = {1},
     year = {2015},
     doi = {10.4064/cm139-1-6},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/cm139-1-6/}
}