@Article{ neg08, author = { Negri, Matteo }, title = { A comparative analysis on variational models for quasi-static brittle crack propagation }, journal = { Adv. Calc. Var. }, year = { 2010 }, volume = { 3 }, pages = { 149-212 }, URL = { http://cvgmt.sns.it/paper/1062/ }, note = { cvgmt preprint} }