The following are useful links to a wide variety of organizations, resources and publications on the web.

NEC* adoption maps - National Electrical Code*
https://www.nfpa.org/nec/nec-adoption-and-use/nec-adoption-maps

IEEE - Institute of Electrical and Electronics Engineers
https://www.ieee.org/

NEMA - National Electrical Manufacturers Association
https://www.nema.org/Pages/default.aspx

IEC - International Electrotechnical Commission
https://www.iec.ch/

ANSI - American National Standards Institute
https://www.ansi.org/

CSA - Canadian Standards Association
https://www.csagroup.org/

UL - Underwriters Laboratories
https://ul.com/

NFPA - National Fire Protection Association
https://www.nfpa.org/