Groups and monoids
An effective version of Stallings' theorem in the case of context-free groups.
(In proceedings ICALP'93).
On the finite subgroups of a context-free group.
(In DIMACS series in Discrete Maths and Theoretical Computer Science, vol. 25,1996)
Semi-groups acting on context-free graphs.
(LaBRI internal report nr 1094-95; short version in proceedings ICALP'96)
Equations in free inverse monoids.
(In IJAC; with T. Deis and J. Meakin)
talk (.pdf)
When is a Graph Product of Groups virtually free ?
(In Communications in Algebra; with M. Lohrey)
Rational subsets of HNN extensions.
(with M. Lohrey; in IJAC; short version in proceedings ICALP'06, LNCS 4052, p. 504-515)
talk (.pdf)
Equations in HNN extensions.
(Manuscript; with M. Lohrey; short version in proceedings ICALP'06)
talk (.pdf)
Positive theories of HNN extensions and amalgamated free products.
(Manuscript; with M. Lohrey; short version in proceedings ICALP'06)
Higher-order pushdowns and monoids .
talk (.pdf)
(Advanced seminar given at SATA'08, Lisbon)