Dreier, H.
view article (9.993612)
German Standards, Safety Regulations and PTB Approval Requirements for Explosion Protected Electrical Equipment.
Physikalisch-Technische Bundesanstalt (PTB), Braunschweig, West Germany
Monograph 113,
Instrument Society of America (ISA). Electrical Safety Practices. Monograph 113. November 1971,
Wilmington, DE,
McKinney, A. H., Editors,
97-101 p.,
1971