%0 Journal Article %T Lectures on four-dimensional Dehn twists %A Paul Seidel %J Mathematics %D 2003 %I arXiv %X These are notes from the 2003 C.I.M.E. summer school "symplectic 4-manifolds and algebraic surfaces". They cover the same material as the author's (by now ancient) Ph.D. thesis. %U http://arxiv.org/abs/math/0309012v3