<ul><li><a href=http://www.legislation.gov.uk/ukpga/2003/21/contents target=_blank>Communications Act(Communications Act 2003, last updated in July 2003, s. 74)</a></li><li><a href=https://www.ofcom.org.uk/__data/assets/pdf_file/0023/256343/unofficial-consolidated-general-conditions-May-2023.pdf target=_blank>OFCOM General conditions of entitlement(in effect from 15 May 2023, Part 1A)</a></li><li><a href=https://www.ofcom.org.uk/__data/assets/pdf_file/0020/108353/final-statement-narrowband-market-review.pdf target=_blank>Wholesale Voice Markets Review 2021-26</a></li></ul>