@article{10_2140_agt_2004_4_407,
     author = {Bunke, Ulrich and Turner, Paul and Willerton, Simon},
     title = {Gerbes and homotopy quantum field theories},
     journal = {Algebraic and Geometric Topology},
     pages = {407--437},
     year = {2004},
     volume = {4},
     number = {1},
     doi = {10.2140/agt.2004.4.407},
     url = {http://geodesic.mathdoc.fr/articles/10.2140/agt.2004.4.407/}
}