@InProceedings{Sti_j2000, author = {Ralf~Stiebe}, title = {Slender matrix languages}, booktitle = {Developments in Language Theory, Foundations, Applications, and Perspectives, Aachen, Germany, 6--9 July 1999}, year = 2000, pages = {375--385}, editor = {Grzegorz~Rozenberg and Wolfgang~Thomas}, publisher = worldsci }