Usability and the User Experience
http://www.goodusability.co.uk/2009/03/usability-and-the-user-experience/

Hamill, David
Good Usability
2009

Abstract:

What’s the difference between usability and user experience? For me, user experience is the experience someone has when using a design. Usability is the extent to which the design provides a good user experience. Usability is often misunderstood to mean ‘ease of use’. It’s much more than this though.