@article{IM_1995__122_3_144320,
     author = {M. Artin and J.T. Stafford},
     title = {Noncommutative graded domains with quadratic.},
     journal = {Inventiones mathematicae},
     pages = {231--276},
     publisher = {mathdoc},
     volume = {122},
     number = {3},
     year = {1995},
     zbl = {0849.16022},
     url = {http://geodesic.mathdoc.fr/item/IM_1995__122_3_144320/}
}