https://app.knowbase.one/vault/rfc/docid/4334
RFC3966: The tel URI for Telephone Numbers
Network Working Group H. Schulzrinne Request for Comments: 3966 Columbia University Obsoletes: 2806 December 2004 Category: Standards Track The tel URI for Telephone Nu...
https://app.knowbase.one/vault/rfc/docid/5353
RFC4904: Representing Trunk Groups in tel/sip Uniform Resource Identifiers (URIs)
Network Working Group V. Gurbani Request for Comments: 4904 Bell Laboratories, Alcatel-Lucent Category: Standards Track C. Jennings Cisco Systems ...