1. Theory of traces;Aalbersberg,1985
2. Trace languages defined by regular string languages;Aalbersberg;Rairo Inform. Théor.,1986
3. Comportement de processus;Arnold,1982
4. Transductions and Context-free Languages;Berstel,1979
5. Problèmes Combinatoires de Commutation et Réarrangements;Cartier,1969