The book that lists 400 different triangle centers is entitled ** Triangle Centers and Central Triangles**, or just

**
1. The Launch Pad: Traditional Triangle Geometry
2. Definitions
3. Centers 1 to 180
4. Centers 181 to 360
5. Central Lines
6. Central Triangles
7. Classes of Triangles
8. Circles and Other Curves
9. New Kinds of Problems**

The book opens with an exciting **Foreword by Douglas Hofstadter** (winner of a Pulitzer Prize for his *Gödel, Escher, Bach: An Eternal Golden Braid*), and closes with a detailed Index. You can order a copy of TCCT from

Utilitas Mathematica Publishing, Inc.

Box 272, St Norbert Postal Station

Winnipeg, MB

Canada R3V 1L6

The cost is US $42.50. This covers surface mail, but you can receive the book by airmail for an additional $5.00. Payment must be by check in US dollars or the equivalent of $42.00 in Canadian dollars. Be sure to specify all the required information: *Triangle Centers and Central Triangles,* by Clark Kimberling, volume 129 of *Congressus Numerantium*.

Encyclopedia of Triangle Centers