GCT Guide, an online companion to the text (and still being developed). The guide provides web-based computational tools (Sage cells) to help with calculations, as well as Geogebra activities to engage the reader with compass and ruler constructions used throughout the text.
Figures with TikZ. This page offers TikZ code for many of the figures found in the text.
Bound copy errata. A list of errors appearing in the bound copy for purchase at Amazon. (These errors have been corrected in the current online version of text.)
