TY - JOUR AU - Emanuele Paolini AU - Eugene Stepanov TI - Optimal transportation networks as flat chains JO - Interfaces and free boundaries PY - 2006 SP - 393 EP - 436 VL - 8 IS - 4 UR - http://geodesic.mathdoc.fr/articles/10.4171/ifb/149/ DO - 10.4171/ifb/149 ID - 10_4171_ifb_149 ER -