Proper noun
EPSG
(historical, 1986–2005) Initialism of European Petroleum Survey Group, now part of IOGP.
Ethernet POWERLINK Standardisation Group (2012), EPSG Working Draft Proposal 301: Ethernet POWERLINK Communication Profile Specification Version 1.1.4, chapter 6.1.1. Source: Internet
I think the link you pointed me to is probably the solution, but I don't know what my source EPSG is. Source: Internet