@article{SIGMA_2012_8_a1,
     author = {Benjamin Bahr and Rodolfo Gambini and Jorge Pullin},
     title = {Discretisations, constraints and diffeomorphisms in quantum gravity},
     journal = {Symmetry, integrability and geometry: methods and applications},
     year = {2012},
     volume = {8},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SIGMA_2012_8_a1/}
}