Great Britain. War Office and Air Ministry. General Staff, Geographical Section. D. Survey. Series K 921 (GSGS 8062). "Refer to this map as Series K921, Sheet Tripoli–El Mina, Edition 2 - GSGS." Edition 1 - GSGS reproduced PDR/1513/3998/1951. Edition 2 - GSGS revised from miscellaneous information up to 1958. In lower right margin: Printed by No 1 SPC, RE 1000/7/58/3899/R. Relief shown by form lines.