# Recommendation I.251.4 (11/1988): Number identification supplementary services: Calling Line Identification Restriction (CLIR)

> superseded recommendation/international standard from the International Telecommunication Union

**Wikidata**: [Q26985373](https://www.wikidata.org/wiki/Q26985373)  
**Source**: https://4ort.xyz/entity/recommendation-i-251-4-11-1988-number-identification-supplementary-services-calling-line-identification-restriction-clir-