@book {9783862007639, 
	title = "break your limits",
	author = "Bücher, Norman",
	isbn = "9783862007639",
	year = "2012",
	edition = "1",
	keywords = "Motivation, Selbstmanagement, Sport, Extremsport, Extremläufer, Grenzerfahrung, Marathon, Ultramarathon",
	url = "http://www.content-select.com/index.php?id=bib_view&ean=9783862007639",
	url = "https://content-select.com/de/portal/media/view/562a0159-e848-4de1-8b5d-191fb0dd2d03",
	publisher = "GABAL",
	language = "ger",
}