The Joy of Sketch: Explorations in Hand-Crafted Visuals
http://www.adaptivepath.com/ideas/essays/archives/000997.php

Rutter, Kate
Adaptive Path
2008

Abstract:

There’s always been a strong visual element to our work: architecture diagrams, interface wireframes, concept models, system and service models. And we’ve become adept at the computer applications that help us create these things. But there are other tools out there, such as the simple tools of pen, paper and sketching.