Perspectives

All articles copyrighted West (a Thomson business), except where otherwise expressly indicated. Except as otherwise expressly provided, the author of each article in this issue has granted permission for copies of that article to be made for educational use, provided that (1) copies are distributed at or below cost, (2) author and journal are identified, (3) proper notice of copyright is affixed to each copy, and (4) the editor of Perspectives is notified of the use. For articles in which it holds copyright, West grants permission for copies to be made for educational use under the same conditions.