ETSI TS 103 479 [1], [LINK]
Next Generation 112 LTD [2], http://www.eena.org/uploads/gallery/files/pdf/2013-03-15-eena_ng_longtermdefinitionupdated.pdf
RFC5985 [3], HTTP-Enabled Location Delivery (HELD),  https://tools.ietf.org/html/rfc5985
RFC6753 [4], A Location Dereference Protocol Using HTTP-Enabled Location Delivery (HELD), https://tools.ietf.org/html/rfc6753
RFC5222 [5], LoST: A Location-to-Service Translation Protocol, https://tools.ietf.org/html/rfc5222"
RFC3261 [6], SIP: Session Initiation Protocol, https://tools.ietf.org/html/rfc3261
RFC5301 [7], A Uniform Resource Name (URN) for Emergency and Other Well-Known Services, https://tools.ietf.org/html/rfc5031
RFC5491 [8], GEOPRIV Presence Information Data Format Location Object (PIDF-LO) Usage Clarification
RFC5808 [9], Requirements for a Location-by-Reference Mechanism