"The Scanning Tunneling Microscope." Gerd Binnig and Heinrich Rohrer. Scientific American, August 1985, page 50.
Burleigh Instruments, Inc. Burleigh Instructional STM Workbook. R.J. Miller et al. (1994) p. 2-12.
Tipler, Paul A. Modern Physics. Wortham Publishers, Inc., New York. 1969.
Sandin, T.R. Essentials of Modern Physics. Addison Wesley Publishing Co., New York. 1989.