The InternetRequest for Comment document about Tags for the Identification of Languages (ftp://ftp.rfc-editor.org/in-notes/rfc3066.txt). It provides a way to register extensions of codes for language names in ISO 639. The current reviewer of new tags and maintainer of the registry is Michael Everson (http://www.evertype.com/standards/iso639/iana-lang-assignments). An alternative for language codes is the Ethnologue.
... in the town. The population density is 1,533.8/km² (3,985.3/mi²). There are 1,784 housing units at an average density of 485.1/km² (1,260.4/mi²). ...