INDEXING STANDARDS
NISO
Anderson, James D. 1997. NISO-TR02, Guidelines for indexes and related information retrieval devices.
https://www.niso.org/publications/niso-tr02-1997-guidelines-indexes-and-related-information-retrieval-devices
Wellisch, Hans 1999. NISO-TR03, Guidelines for alphabetical arrangement of letters and sorting of numerals and other symbols.
https://www.niso.org/publications/niso-tr03-1999-guidelines-alphabetical-arrangement-letters-sorting-numerals-other
ISO
ISO 999:1996, Information and documentation – guidelines for the content, organization and presentation of indexes.
Available for purchase at: https://www.iso.org/standard/5446.html
ISO 5963:1985, Documentation – Methods for examining documents, determining their subjects, and selecting indexing terms.
Available for purchase at: https://www.iso.org/standard/12158.html
THESAURUS STANDARDS
NISO
ANSI/NISO Z39.19-2005 (R2010) Guidelines for the Construction, Format, and Management of Monolingual Controlled Vocabularies.
https://www.niso.org/publications/ansiniso-z3919-2005-r2010
ISO
ISO 25964-1: 2011 Information and documentation - Thesauri and interoperability with other vocabularies - Part 1: Thesauri for information retrieval.
Available for purchase at: https://www.iso.org/standard/53657.html
ISO 25964-2: 2013 Information and documentation – Thesauri and interoperability with other vocabularies – Part 2: Interoperability with other vocabularies.
Available for purchase at: https://www.iso.org/standard/53658.html