NISO
Anderson, James D. 1997. NISO-TR02, Guidelines for indexes and related information retrieval devices.
http://www.niso.org/publications/tr/tr02.pdf
Wellisch, Hans 1999. NISO-TR03, Guidelines for alphabetical arrangement of letters and sorting of numerals and other symbols.
http://www.niso.org/publications/tr/tr03.pdf.
ISO
ISO 999:1996, Information and documentation—guidelines for the content, organization and presentation of indexes.
Available for purchase at: http://www.iso.org/iso/search.htm?qt=organization+of+indexes&published=on&active_tab=standards
As adopted and/or translated in various countries
Australia/New Zealand: AS/NZS999 United Kingdom: BS3700:1988 China: GB/T 22466-2008 France: NF Z47-102 Germany: DIN 31630
Related
ISO 25964-1: 2011 Information and documentation – Thesauri and interoperability with other vocabularies – Part 1: Thesauri for information retrieval.
Available for purchase at: http://www.iso.org/iso/search.htm?qt=25964&published=on&active_tab=standards