in Springer Proceedings in Mathematics and Statistics, ISSN: 2194-1009
Volume: 60, Pages: 427-431
Conference
Spanish Relativity Meeting, Ere 2012, Date: 3 September 2012 through 7 September 2012, Location: Guimaraes, Sponsors: Centro de Matematica;Escola de Ciencias;et al;FCT;SEGRE;Universidade do Minho