Bibliography: 
Cameron, H. L., 1952 "The Measurement 
of Water Current Velocities by 
Parallax Methods", Photogrammetric 
Engineering, March 1952 pp 99-104 
Forrester, #. D. and Cross, C.M., 
"Plotting of Water Current Patterns 
by Fhotogrammetry". Paper given at 
26 Annual Meeting, American Society 
of Photogrammetry, Jashington D.C. 
March 25, 1960