@article {, title = {Sistema sensor para la detecci{\'o}n de objetos/obst{\'a}culos en puntos cr{\'\i}ticos de l{\'\i}neas f{\'e}rreas.}, volume = {P201000354}, year = {2013}, month = {03/2013}, address = {Espa{\~n}a}, author = {D. Pizarro and M. Marr{\'o}n and A. Gardel and Mazo, M. and F. J. Rodriguez and I. Bravo and S. E. Palazuelos} }