This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Merwede map. Encyclopdia Britannica th ed 's Map article as the first fullscale use of isobath lines library uu nl php obj lan en page De Rivier de Merwede van ontrent de Steenenhoek Oostwaardsop tot verby het dorp van Sleeuwyk held by the University of Utrecht Nicolas Samuelson Cruquius nl Nicolaas Samuelszoon Kruik la Nicolaus