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A lot of statements made in this article are wrong / partially wrong. I just modified the content of sample size limits. -- Thomas M Bernhard ( talk) 18:36, 10 June 2015 (UTC) reply

A lot of statements are repeated inside the article. I suggest cleanup of this article.

I'd like to read about photoelectron diffraction. Arnero 17:00, 16 April 2007 (UTC) reply

This article was automatically assessed because at least one WikiProject had rated the article as start, and the rating on other projects was brought up to start class. BetacommandBot 10:06, 10 November 2007 (UTC) reply