@book{91608,
	author = {Mader, Friedrich Wilhelm, and Egler, Willi,},
	title = {Wunderwelten :},
	publisher = {Project Gutenberg,},
	year = {2015},
	address = {Salt Lake City, UT :},
	note = {Wikipedia page about this book: https://de.wikipedia.org/wiki/Wunderwelten},
	url = {https://www.gutenberg.org/ebooks/50770}
}