@PhdthesisMisc{B09_847, author = {Benedikt Zeller}, title = {The spherically symmetric Einstein-Dirac system}, note = {Dis_no 18672, Prof. Dr. Ralf Hiptmair}, school = {ETH Z{\"u}rich}, doi = {http://dx.doi.org/10.3929/ethz-a-006039115}, year = {2009} }