R. W. FAAS; S. WARTEL. Mud is transported to the Dutch delta area from the Rhine, Waal, Maas and Scheldt rivers (resp. 0,6; 2,5; 0,7 and 0,7 million tons/year). Above, in the Rotterdam Waterway about 3,5 million tons of mud per year are brought in from the sea. The mud of the u. Netherlands Journal of Geosciences, p. 211-218, 1 Jan. 1977.