1. Transductions and Context-free Languages;Berstel;B.G. Teubner, Stuttgart,1979
2. Analysis of a class of algorithms for problems on trace languages;Bertoni,1988
3. Problèmes combinatoires de commutation et réarrangements;Cartier,1969
4. Free partially commutative monoids;Choffrut,1986
5. Transitive orientations, Möbius functions and complete semi-Thue systems for free partially commutative monoids;Diekert,1988