1、National Library of Standards(NLS)、National Digital Library of Standards:https://www.nssi.org.cn/nssi/front/index.jsp;

2、China standard service network:https://www.cssn.net.cn/cssn/index；

3、International Organization for Standardization:https://www.iso.org/home.html；

4、International Electrotechnical Commission:https://webstore.iec.ch/。