Index to Directorate of Colonial Surveys topographic maps of Nyasaland : D.C.S. 25 - 1:50,000.
[Teddington] : Directorate of Colonial Surveys,
1955.
"Published up to April 1953"
"Map 4".
"Also showing areas geological mapped on 1:50,000 scale up to 1953, and Distribution of mineral deposits"