@misc{EP_2015_50_a0,
     title = {Pr\'eface},
     journal = {ESAIM. Proceedings},
     pages = {I--I},
     publisher = {mathdoc},
     volume = {50},
     year = {2015},
     doi = {10.1051/proc/20155000f},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.1051/proc/20155000f/}
}