References

Acknowledgements
An expert is someone who knows some of the worst mistakes that can be made in his subject, and how to avoid them.
—Werner Heisenberg (1901–1976)

Several people have helped with this project. Some have made significant contributions by writing portions, taping videos, or creating Geometer's Sketchpad sketches. Others have helped by proofreading or by making constructive suggestions for formatting. In the end, all errors are solely my responsibility.

Student Contributions.
Jessica Trautwein taped several video lectures and proofread pages as part of her honors apprenticeship.
Jessica Mavis prepared several Geometer's Sketchpad sketches and video lectures as part of her honors apprenticeship.
Nancy Martin wrote the chapter historical overviews.
Lindsey Carlson taped a video lecture.
A special thanks needs to go to the students who experienced the first draft of the book. They provided many helpful suggestions and corrections. Those making suggestions were Arick Follingstad, Nick Howell, Dan Lawson, Nancy Martin, Jessica Mavis, Rosanne Pfenning, Heather Prestegord, Alicia Stevenson, and Jessica Trautwein.
Additional students who have made significant contributions: Andria Kelly and Jordan Cieslak.

Others
Barb Rath made many constructive suggestions that improved readability.
Dr. Dennis Rhoads proofread parts.
Dr. Damiano Fulghesus made many constructive suggestions.

Tech Support
Barb Hoppe and Dr. Rhonda Ficek helped with many of the technological problems that occurred and made constructive suggestions for formatting the webpages.