@book{101976,
	author = {Hodgson, Fred T. and Williams, Morris},
	title = {Stair-building and the steel square},
	publisher = {Project Gutenberg,},
	year = {2020},
	address = {Salt Lake City, UT :},
	note = {Release date is 2020-01-11},
	url = {https://www.gutenberg.org/ebooks/61150}
}