@book{91520,
	author = {Evans, E. Everett},
	title = {The Planet Mappers},
	publisher = {Project Gutenberg,},
	year = {2015},
	address = {Salt Lake City, UT :},
	note = {Release date is 2015-12-13},
	url = {https://www.gutenberg.org/ebooks/50682}
}