@article{SIGMA_2012_8_a14,
     author = {Enrique F. Borja and I\~naki Garay and Francesca Vidotto},
     title = {Learning about quantum gravity with a couple of nodes},
     journal = {Symmetry, integrability and geometry: methods and applications},
     year = {2012},
     volume = {8},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SIGMA_2012_8_a14/}
}