Cosmic Ray Exposure Ages for Almahata Sitta Non-Ureilite Samples Meier, M. M. M. ; Welten, K. C. ; Jenniskens, P. ; Baur, H. ; Wieler, R. Abstract Publication: Meteoritics and Planetary Science Supplement Pub Date: September 2010 Bibcode: 2010M&PSA..73.5253M