Many people helped with the development of this text. Jeff Weeks' text The Shape of Space inspired me to first teach a geometry course motivated by cosmic topology. Colleagues at The College of Idaho encouraged me to teach the course repeatedly as the manuscript developed, and students there provided valuable feedback on how this story can be better told.
I would like to thank Rob Beezer, David Farmer, and all my colleagues at the UTMOST 2017 Textbook Workshop and in the PreTeXt Community for helping me convert my dusty tex code to a workable PreTeXt document in order to make the text freely available online, both as a webpage and as a printable document. I also thank Jennifer Nordstrom for encouraging me to use PreTeXt in the first place.
I owe my colleagues at The College of Idaho and the University of Oregon a debt of gratitude for helping to facilitate a sabbatical during which an earlier incarnation of this text developed and was subsequently published in 2009 with Jones & Bartlett. Richard Koch discussed some of its content with me, and Jim Dull patiently discussed astrophysics and cosmology with me at a moment's notice.
The pursuit of detecting the shape of the universe has rapidly evolved over the last twenty years, and Marcelo Rebouças kindly answered my questions regarding the content of Chapter 8 back in 2008, and pointed me to the latest papers. I am also grateful to the authors of the many cosmology papers accessible to the amateur enthusiast and written with the intent to inform.
Finally, I would like to thank my family for their support during this endeavor, for letting this project permeate our home, and for encouraging its completion when we might have done something else, again.