@article{CC_2008_37_2_a9,
     author = {Oberle, Hans Joachim and Rosendahl, Ricki},
     title = {On singular arcs in nonsmooth optimal control},
     journal = {Control and Cybernetics},
     pages = {429--450},
     year = {2008},
     volume = {37},
     number = {2},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CC_2008_37_2_a9/}
}