@inproceedings{29472, author = {{Gehler, M. and Ober-Blöbaum, Sina and Dachwald, B. and Marsden, J.E.}}, booktitle = {{1st IAA Planetary Defense Conference: Protecting Earth from Asteroids}}, location = {{Granada, Spain}}, title = {{{Optimal control of gravity tractor spacecraft near arbitrarily shaped asteroids}}}, year = {{2009}}, }