@article{ASNSP_2003_5_2_4_631_0,
     author = {Buttazzo, Giuseppe and Stepanov, Eugene},
     title = {Optimal transportation networks as free {Dirichlet} regions for the {Monge-Kantorovich} problem},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     pages = {631--678},
     publisher = {Scuola normale superiore},
     volume = {Ser. 5, 2},
     number = {4},
     year = {2003},
     mrnumber = {2040639},
     zbl = {1127.49031},
     language = {en},
     url = {http://www.numdam.org/item/ASNSP_2003_5_2_4_631_0/}
}