@article{JEMS_2016_18_6_a3,
     author = {Christoph Wockel and Chenchang Zhu},
     title = {Integrating central extensions of {Lie} algebras via {Lie} 2-groups},
     journal = {Journal of the European Mathematical Society},
     pages = {1273--1320},
     publisher = {mathdoc},
     volume = {18},
     number = {6},
     year = {2016},
     doi = {10.4171/jems/613},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/jems/613/}
}