@book{32689,
	author = {Fink, Wolfgang, ed.},
	title = {Space Exploration Technologies II},
	publisher = {SPIE},
	year = {2009},
	series = {Proceedings of SPIE; V. 7331},
	address = {Washington, USA},
	url = {https://www.spiedigitallibrary.org/conference-proceedings-of-spie/7331}
}