These lists are just a start, but a big thanks to Maura Smale - her game was a big inspiration for ours - and to Gary Maixner from Ferris State University (who I met at LOEX 2018 at his and Mari Kermit-Canfield's presentation and at the Gaming Roundtable at lunch, and who gave me the names of some good articles/books on game design).
On Gamification
Gamification in Education and Libraries. (2015). Library Technology Reports, 51(2), 20-28.
McMunn-Tetangco, E. (2017). Gamification : a practical guide for librarians. Lanham : Rowman & Littlefield, [2017].
Nicholson, S. SNAP Model for Immersive Escape Room Design - Quick Reference. Retrieved from http://scottnicholson.com/pubs/SNAPstarter.pdf
Smale, M. (2015). Play a Game, Make a Game: Getting Creative with Professional Development for Library Instruction. The Journal of Creative Library Practice. [online] Available at: http://creativelibrarypractice.org/2015/05/18/play-a-game-make-a-game/ [Accessed 1 May 2018].
On Games and Learning
Gee, J. P. (2005). Learning by Design: Good Video Games as Learning Machines. E-Learning, 2(1), 5-16.
Gee, J. P. (2007). What video games have to teach us about learning and literacy. New York : Palgrave Macmillan.
Ham, E. (2016). Tabletop game design for video game designers. Burlington: Focal Press.
McGonigal, J. (2011). Reality is broken: Why games make us better and how they can change the world. New York, NY, US: Penguin Press.
Schell, J. (2008). The art of game design: A book of lenses. Burlington: Morgan Kaufmann.
Squire, K. (2011). Video games and learning: Teaching and participatory culture in the digital age. Technology, Education--Connections (the TEC Series). Teachers College Press.
On Design Thinking
Thanks to the people who taught us to throw ideas out there and see if they work.