@article{10_2140_agt_2004_4_1211,
     author = {Jacobsson, Magnus},
     title = {An invariant of link cobordisms from {Khovanov} homology},
     journal = {Algebraic and Geometric Topology},
     pages = {1211--1251},
     year = {2004},
     volume = {4},
     number = {2},
     doi = {10.2140/agt.2004.4.1211},
     url = {http://geodesic.mathdoc.fr/articles/10.2140/agt.2004.4.1211/}
}