Card Sorting: A Definitive Guide
http://www.boxesandarrows.com/archives/card_sorting_a_definitive_guide.php

Maurer, Donna and Todd Warfel
Boxes and Arrows
2004

Abstract:

Card sorting is a simple user-centered technique for obtaining insight into the structure of a site. But is it really so simple? This definitive guide to card sorting includes detailed instructions on how to execute and analyze a sort, plus helpful hints to improve your sorts. It is the first in a series of articles about card sorting.