1. drainage Datasets Harvard University Restricted content Environmental Systems Research Institute, Inc. This layer contains line features representing the major drainage systems of the world.
2. ESRI Data & Maps 2004 : World Rivers Datasets Harvard University Restricted content 1992. Environmental Systems Research Institute (Redlands, Calif.). World Rivers represents the major rivers within the world. ESRI.
3. World Rivers : Esri Data & Maps 2012 Datasets Harvard University Restricted content 1992. Environmental Systems Research Institute (Redlands, Calif.). World Rivers represents the major rivers within the world. Esri.