2007DIN EN ISO 13443:2007-09 Natural gas - Standard reference conditions (ISO 13443:1996, including Corrigendum 1:1997); German version EN ISO 13443:2005
2007DIN EN ISO 13443:2007 Natural gas - Standard reference conditions (ISO 13443:1996, including Corrigendum 1:1997); English version of DIN EN ISO 13443:2007-09