Codes for the Representation of the Names of Languages Documents the essential information from ISO 639, Codes for the Representation of the Names of Languages. http://www.oasis-open.org/cover/iso639a.html
ISO 639-1 and ISO 639-2: International Standards for Language Codes. ISO 15924: International Standard for names of scripts - 65th IFLA Council and General Conference - Conference Programme and Proceedings An overview and history of the standard. http://www.ifla.org/IV/ifla65/papers/099-155e.htm