@article{10_1090_S0894_0347_09_00642_0,
     author = {Calegari, Danny and Freedman, Michael and Walker, Kevin},
     title = {Positivity of the universal pairing in 3 dimensions},
     journal = {Journal of the American Mathematical Society},
     pages = {107--188},
     publisher = {mathdoc},
     volume = {23},
     number = {1},
     year = {2010},
     doi = {10.1090/S0894-0347-09-00642-0},
     url = {http://geodesic.mathdoc.fr/articles/10.1090/S0894-0347-09-00642-0/}
}