International records / UK National Archives
NIGERIA 1:50,000 CHAD (D.O.S. 430) : authority for mapping, area of mapping, general material, diagrams, map material, reports, sheet names, administrative breakdown, instructions, gaps in air photo cover.
CCS/DOS/297/3 | The Charles Close Society Archives Catalogue.Ordnance Survey International.
No file is held for this record yet. The catalogue entry and the link to where it was published are kept.
