Examining the Legibility of the Number '1' and the '÷' Symbol
http://www.surl.org/usabilitynews/101/legibility.asp

Fox, Doug, Barbara S. Chaparro and Ed Merkle
Usability News
2008

Abstract:

This article continues the investigation of the legibility of onscreen typefaces and the influence of individual character features on correct identification. Specific attributes of alphanumeric characters and symbols shown to be the least legible were measured and analyzed using a statistical method called classification tree analysis. Results from this analysis for the number "1" and the "÷" symbol are discussed.