Citations
Ordnance Survey information : leaflet no 31. Triangulation and lower order control information, 1988-04, GBR/3296/Maps/CCSA.OS_143_18/13, OS_143_18/13. Cambridge University Library. |
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Ordnance Survey information : leaflet no 31. Triangulation and lower order control information, 1988-04, GBR/3296/Maps/CCSA.OS_143_18/13, OS_143_18/13. Cambridge University Library. https://archivesearch.lib.cam.ac.uk/repositories/2/archival_objects/243104 Accessed April 29, 2025. |