Behrens, Stefan Max Planck Institute for Mathematics, Max Planck Society;
Behrens_on 4-manifolds_oa_2013.pdf (Any fulltext), 807KB
Behrens, S. (2013). On 4-manifolds, folds and cusps. Pacific Journal of Mathematics, 264(2), 257-306. doi:10.2140/pjm.2013.264.257.