@article{TAC_2006_16_a17,
     author = {R. J. MacG. Dawson and R. Par\'e and D. A. Pronk},
     title = {Paths in  double categories},
     journal = {Theory and applications of categories},
     pages = {460--521},
     publisher = {mathdoc},
     volume = {16},
     year = {2006},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/TAC_2006_16_a17/}
}