Matthias Jantzen.
On a special monoid with a single definig relation.
Theoretical Computer Science, 16:61-73, 1981.
@article{Jantzen81a, Author = {Jantzen, Matthias}, Journal = {Theoretical Computer Science}, Pages = {61--73}, Title = {On a special monoid with a single definig relation}, Volume = 16, Year = 1981 }