Alexandru Dinca. The Metric Properties on the Semigroups and the Languages. In Antoni W. Mazurkiewicz, editor, Mathematical Foundations of Computer Science 1976, 5th Symposium, Gdansk, Poland, September 6-10, 1976, Proceedings. Volume 45 of Lecture Notes in Computer Science, pages 260-264, Springer, 1976.
Abstract is missing.