Goldstein, Joseph (2018). Scanning electron microscopy and x-ray microanalysis. Newbury, Dale E.,, Michael, Joseph R.,, Ritchie, Nicholas W. M.,, Scott, John Henry J.,, Joy, David C. (Fourth ed.). New York, NY: Springer. pp. 115–116. ISBN978-1-4939-6676-9. OCLC1013460027.