Valley, George E. Jr.; Wallman, Henry (1948), Vacuum Tube Amplifiers, MIT Radiation Laboratory Series 18, New York: McGraw-Hill.. Reviews: Ridenour, Louis N. (1948), "Vacuum tube amplifiers", Massachusetts Institute of Technology Radiation Laboratory Series; Giacoletto, L. J. (1949), "Institute News and Radio Notes", Proceedings of the I.R.E., 37 (8): 907, doi:10.1109/JRPROC.1949.229980; Frankland, Scott (1998), Vacuum tube electronics: Reviews of the major texts(PDF), Perkins Electro-Acoustical Research Laboratory.
Johansson, Magnus (1996), "Early analog computers in Sweden—with examples from Chalmers University of Technology and the Swedish Aerospace Industry", IEEE Annals of the History of Computing, 18 (4): 27–33, doi:10.1109/85.539913.
Valley, George E. Jr.; Wallman, Henry (1948), Vacuum Tube Amplifiers, MIT Radiation Laboratory Series 18, New York: McGraw-Hill.. Reviews: Ridenour, Louis N. (1948), "Vacuum tube amplifiers", Massachusetts Institute of Technology Radiation Laboratory Series; Giacoletto, L. J. (1949), "Institute News and Radio Notes", Proceedings of the I.R.E., 37 (8): 907, doi:10.1109/JRPROC.1949.229980; Frankland, Scott (1998), Vacuum tube electronics: Reviews of the major texts(PDF), Perkins Electro-Acoustical Research Laboratory.
