Air carrier First Officer reported being unable to find the POM VOR which was required for a procedure; and could only find POM as a waypoint through multiple sources.

Narrative

This is in regards to the single engine / engine out 'T PROC' for Runway 6 at Naples; Italy (NAP/LIRN). Upon reviewing the preliminary takeoff data during flight deck preflight preparations for our flight to ZZZ departing Runway 6 at NAP; the 'T PROC' for Runway 6 came into question; scrutiny; and clarification. The 'T PROC' reads 'TRK RCL TO POM VOR. TURN LT TO INTCPT SOR VOR R-360. TRK INBND. HOLD SE SOR ON R-180 INBD RT TURNS. ACCEL ALT: 1100 MSL. While attempting to set up this procedure both in the FMC; flight management computer; on the legs 2 page; the FIX pages; and while selecting the POM VOR frequency on the VOR panel; it was discovered that the POM VOR for this procedure could not be located. Looking through multiple sources within JEPP FD PRO; NAP SID; standard instrument departure; STAR; standard terminal arrival; approach plates; as well as the HIGH; LOW; & VFR enroute charts in the vicinity of NAP; the POM VOR was not to be found.While conducting a search within JEPP FD PRO for POM; a waypoint was discovered off the departure end of Runway 6 at NAP. However; a POM waypoint was discovered instead. Further research by the Captain utilizing an 'internet' search; he was able to find information about the POM VOR; namely the latitude and longitude coordinates. We compared those coordinates with the discovered POM 'waypoint' coordinates and they were quite similar but still not convinced that we could utilize this information to comply with the 'T PROC' as written. For further assistance and clarification; both our Dispatcher and the Chief Pilot were conferenced utilizing our SATCOM; satellite communications. All were in agreement that this did pose a challenge and the Chief Pilot recalled an allowance within the FOM; flight operations manual; to substitute identification in this event. We were referenced to FOM; NAVAID Out of Service. We had a high degree of confidence that the POM waypoint was now the position and place holder for the previously commissioned POM VOR. However; the question remains as to when was the POM VOR decommissioned and the POM waypoint created. We concluded that the POM waypoint could be utilized and loaded in the FMC FIX page for identification; then completed our departure briefing noting the POM waypoint utilization.Upon further research while conducting an 'internet' search for 'POM VOR' and 'Pomigliano VOR;' I came across many website references to its existence; frequency; and even SID and STAR charts as its title name. However; the one website that I came across appeared to have outdated data; specifically the SID and STAR because that did not match up with the same for NAP/LIRN in JEPP FD PRO installed on our EFB (current). This website was Airport & FBO Info for LIRN; fltplan.com. During my extended research opportunity; I came across a Jeppesen approach plate for the ILS Z Runway 24 (11-4) into NAP/LIRN dated a few years ago; in which the POM was depicted on the chart view; plan view; and part of the missed approach procedure. Additionally; I discovered that not only was POM a VOR but also a NDB at one point; nearly co-located with the VOR. Also found information at www.naples-airport.info/airport-data/ that indicates POM VOR."