Hudson Bay. Surface water supply of United States, 1941: pt. 5, Hudson Bay and upper Mississippi River basin: prepared under direction of Glenn L. Parker, chief hydraulic engineer, H. C. Beckman, F. C. Christopherson, D. M. Corbett, L. C. Crawford, H. E. Grosbach, J. H. Morgan, P. R. Speer, and A. H. Tuttle, district engineers.