"This publication, the sixth in this series issued by the Federal Power Commission, presents data as of January 1, 1972, on the capacity, generation, and other characteristics of the developed and undeveloped hydroelectric power resources of the United States. Principal statistics are shown by major drainages and river basins and by geographic divisions and States"--Page iii.

"This publication, the seventh in this series issued by the Federal Power Commission, presents data as of January 1, 1976, on the capacity, generation, and other characteristics of the developed and undeveloped hydroelectric power resources of the United States. Principal statistics are shown by major drainages and river basins and by geographic divisions and States"--Page iii.