@book{91711,
	author = {Ward, Clarence,},
	title = {Mediaeval Church Vaulting},
	publisher = {Project Gutenberg,},
	year = {2016},
	address = {Salt Lake City, UT :},
	note = {Release date is 2016-01-07},
	url = {https://www.gutenberg.org/ebooks/50873}
}