Design of and protective provisions for electrical power installations in depots and workshops for urban DC rail systems / VDV, die Verkehrsunternehmen ; overall revision Committee on Electrical Power Installations ; list of authors Dipl.-Ing. (FH) Dietmar Ast, Rail Power Systems, Offenbach, Dr.-Ing. Joachim Dreyer, VBG, Hamburg, Dipl. Ing. (FH) Günther Grüner SWM, Munich, Dipl.-Ing. Jens Pappe, BVG, Berlin, Dipl.-Ing. Jens Perbandt, HOCHBAHN, Hamburg, Dipl.-Ing. Udo Stahlberg, VDV, Cologne, Christoph Wassermann, LVB, Leipzig, Dipl.-Ing. (FH) Joachim Ziemendorf, SYSTRA, Paris