@article{10_2140_agt_2004_4_81,
     author = {Turner, Paul},
     title = {A functorial approach to differential characters},
     journal = {Algebraic and Geometric Topology},
     pages = {81--93},
     year = {2004},
     volume = {4},
     number = {1},
     doi = {10.2140/agt.2004.4.81},
     url = {http://geodesic.mathdoc.fr/articles/10.2140/agt.2004.4.81/}
}