Patrice Ossona de Mendez Michel Pocchiola Dominique Poulalhon Jorge L. Ramírez Alfonsín Gilles Schaeffer 1-4 2008 31 Electronic Notes in Discrete Mathematics http://dx.doi.org/10.1016/j.endm.2008.06.001 db/journals/endm/endm31.html#MendezPPAS08