@book{118770,
	author = {Whitehead, Alfred North, and Russell, Bertrand,},
	title = {Principia mathematica, vol. 1 (of 3)},
	publisher = {Project Gutenberg,},
	year = {2026},
	address = {Salt Lake City, UT :},
	note = {Wikipedia page about this book: https://en.wikipedia.org/wiki/Principia_Mathematica},
	url = {https://catalog.hathitrust.org/Record/000168955}
}