# Document Type Definition

> set of markup declarations that define a document type for an SGML-family markup language

**Wikidata**: [Q212327](https://www.wikidata.org/wiki/Q212327)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Document_type_definition)  
**Source**: https://4ort.xyz/entity/document-type-definition


## References

1. Freebase Data Dumps. 2013
2. [Source](https://pygments.org/docs/lexers/#pygments.lexers.html.DtdLexer)
3. BabelNet
4. Quora
5. [OpenAlex](https://docs.openalex.org/download-snapshot/snapshot-data-format)
6. Wikibase TDKIV