This is a list of the books and sites that I have been using for my research. Most information presented in other blog posts comes from one of the following sources.
Books I have acquired (reviews and thoughts on these books will be posted as I finish them):
Non-Euclidean Geometry: or, three moons in mathesis by Lillian Rosanoff Lieber (print)
Non-Euclidean Geometry: A Critical and Historical Study of Its Development by Roberto Bonola (online)
Euclid's Window: The Story of Geometry from Parallel Lines to Hyperspace by Leonard Mlodinow (print- library)
Introduction to Non-Euclidean Geometry by Harold Wolfe (print-library)
The Call of Cthulhu and Other Weird Stories by H P Lovecraft (print- library)
The Inverted World by Christopher Priest (print)
Relevant books I still plan on acquiring:
Geometry, Relativity, and the Fourth Dimension by Rudolf Rucker
The Fourth Dimension and Non-Euclidean Geometry in Modern Art by Linda Dalrymple Henderson
Other sources:
Hyperbolic Geometry by James W. Cannon, William J. Floyd, Richard Kenyon, and Walter R. Parry (pdf file)
PlanetMath.org
Videos by njwildberger on Youtube, especially the playlist on universal hyperbolic geometry and the non-Euclidean geometry chapter of math history.
The Geometry of Whales and Ants chapter from The Universe in Zero Words: The Story of Mathematics as Told Through Equations by Dana Mackenzie (book)