@InProceedings{	  dm88stacs,
  author	= "Volker Diekert and Axel M{\"o}bus",
  address	= "Heidelberg",
  booktitle	= "Proc. 5th Annual Symposium on Theoretical Aspects of
		  Computer Science (STACS'88), Bordeaux (France), 1988",
  editor	= "R. Cori and others",
  volume	= "294",
  pages		= "126--135",
  publisher	= "Springer-Verlag",
  series	= "Lecture Notes in Computer Science",
  title		= "Hotz-isomorphism theorems in {F}ormal {L}anguage {T}heory",
  year		= "1988",
  doi		= "10.1007/BFb0035839"
}