A.M.S. (Series) ; T531. First edition - AMS 1. Polyconic projection. "The longitude of this sheet is based on the meridian of Batavia." "Redrawn from Wester-Afdeeling van Borneo 1:200,000 Top. Dienst, Sheet XVII-XVIII, 1928. Boundaries revised from Atlas van Tropisch Nederland, 1938."