Portugal 1:50,000.
Great Britain.War Office.General Staff.Geographical Section.
[London] : War Office,
1940-42.
"Contour interval 25 metres.".
Military grid.
Five classes of roads and tracks, three classes of railroads, three types of internal boundaries, and various types of vegetation indicated.
"Glossary" included on some sheets.
Marginal diagrams: Incidence of grid letters and index to adjoining sheets.--[Reliability diagram].
Based on Portuguese maps.
Graphic index in GSGS central file.