@Article{ MasOudVel16, author = { Massaccesi, Annalisa and Oudet, Edouard and Velichkov, Bozhidar }, title = { Numerical Calibration of Steiner trees }, journal = { Appl. Math. Optim. }, year = { 2016 }, pages = { }, URL = { http://cvgmt.sns.it/paper/2995/ }, note = { cvgmt preprint} }