Brower (U.S. Patent1,834,330, W. M. Brower)
Zworykin (I.R.E. Proc., Vol. 17, No. 3, March, 1929, V. Zworykin)
Horton (I.R.E. Proc., Vol. 17, No. 9, September, 1929, J. W. Horton)
Finch (U. S. Patent 1,985,654. W. G. H. Finch)
Fulton (U. S. Patent 1,985,084. Otho Fulton)
(C) Marius Rensen