@article{701626,
     title = {Introduction to algebra over  ``brave new rings''},
     booktitle = {Proceedings of the 18th Winter School "Geometry and Physics"},
     series = {GDML\_Books},
     publisher = {Circolo Matematico di Palermo},
     address = {Palermo},
     year = {1999},
     pages = {49-82},
     mrnumber = {MR1692258},
     zbl = {0969.55003},
     url = {http://dml.mathdoc.fr/item/701626}
}

Vogt, R. M. Introduction to algebra over  “brave new rings”, dans Proceedings of the 18th Winter School "Geometry and Physics", GDML_Books,  (1999), pp. 49-82. http://gdmltest.u-ga.fr/item/701626/