@article{1102637373, author = {Greco, S. and Raciti, G.}, title = {The L\"uroth semigroup of plane algebraic curves.}, journal = {Pacific J. Math.}, volume = {151}, number = {2}, year = {1991}, pages = { 43-56}, language = {en}, url = {http://dml.mathdoc.fr/item/1102637373} }
Greco, S.; Raciti, G. The Lüroth semigroup of plane algebraic curves.. Pacific J. Math., Tome 151 (1991) no. 2, pp. 43-56. http://gdmltest.u-ga.fr/item/1102637373/