Visible speech /
Potter, Ralph Kimball, 1894-
Visible speech / [by] Ralph K. Potter, George A. Kopp and Harriet C. Green. - 1st ed. - New York : D. Van Nostrand Co., 1947. - xvi, 441 p. : ill. ; 28 cm. - Bell Telephone Laboratories series . - Bell Telephone Laboratories series. .
Includes Bibliography and index
Telephone--Equipment and supplies.
621.386 / POV 1947
Visible speech / [by] Ralph K. Potter, George A. Kopp and Harriet C. Green. - 1st ed. - New York : D. Van Nostrand Co., 1947. - xvi, 441 p. : ill. ; 28 cm. - Bell Telephone Laboratories series . - Bell Telephone Laboratories series. .
Includes Bibliography and index
Telephone--Equipment and supplies.
621.386 / POV 1947