User Experience Design: The Evolution of a Multi-Disciplinary Approach
http://www.usabilityprofessionals.org/upa_publications/jus/2008may/mayhew1.html
  peer-reviewed

Mayhew, Deborah J.
Journal of Usability Studies
2008

Abstract:

Easy task completion (traditional usability) is not enough in the Web world. Appealing visual site design is not enough. A site visitor needs to not only be attracted to a site and able to figure out how to buy (or register, sign up, etc.)-they need in addition to be able to tell quickly that a site will meet their needs, and they need to want to buy from this site, as opposed to a competitor's site. This is a key aspect of overall Web site success.