@article{EP_1998_4_a1,
     author = {M. Bergounioux and D. Tiba},
     title = {Optimal control for the obstacle problem with state constraints},
     journal = {ESAIM. Proceedings},
     pages = {7--19},
     publisher = {mathdoc},
     volume = {4},
     year = {1998},
     doi = {10.1051/proc:1998018},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.1051/proc:1998018/}
}