@Article{ belnovrie02a, author = { Bellettini, Giovanni and Novaga, Matteo and Riey, Giuseppe }, title = { First variation of anisotropic energies and crystalline mean curvature for partitions }, journal = { Interfaces Free Bound. }, year = { 2003 }, volume = { 5 }, pages = { 331-356 }, URL = { http://cvgmt.sns.it/paper/993/ }, note = { cvgmt preprint} }