DIN CLC/TS 50131-11 Supplement 1 Alarm systems - Intrusion and hold-up systems - Part 11: Hold-up devices; Supplement 1: Interpretation Sheet 1; German version CLC/TS 50131-11:2012/IS1:2014
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 11/01/2014