No GPS required - geograph.org.uk - 413461.jpg
Nottingham and Barnetby Line, Barnetby Junction to Lincoln Pelham Street Junction
Manchester and Cleethorpes Line, Deepcar to Cleethorpes
Engineer's Line References (ELRs): A (Hopefully) Comprehensive Listing
Railway Codes and Other Data: A (Hopefully) Comprehensive Listing
Network Rail FOI response 27 May 2022: ReferenceLines shapefile
Network Rail FoI response 27 January 2016: Geographical Information on TIPLOCs