@article{10_2140_agt_2008_8_1567,
     author = {Krouglov, Vladimir},
     title = {The curvature of contact structures on 3{\textendash}manifolds},
     journal = {Algebraic and Geometric Topology},
     pages = {1567--1579},
     year = {2008},
     volume = {8},
     number = {3},
     doi = {10.2140/agt.2008.8.1567},
     url = {http://geodesic.mathdoc.fr/articles/10.2140/agt.2008.8.1567/}
}