@article{GDZPPN002224089, title = {On a Class of Preorderrings of Higher Level.}, journal = {Manuscripta mathematica}, volume = {39}, year = {1982}, pages = {163-210}, zbl = {0537.12015}, url = {http://dml.mathdoc.fr/item/GDZPPN002224089} }
Basarab, Serban A. On a Class of Preorderrings of Higher Level.. Manuscripta mathematica, Tome 39 (1982) pp. 163-210. http://gdmltest.u-ga.fr/item/GDZPPN002224089/