Kyte, Frank T.; Shukolyukov, Alex; Hildebrand, Alan R.; Lugmair, Guenter W.; Hanova, Jana (2011): Chromium-isotopes in late Eocene impact spherules indicate a likely asteroid belt provenance. Elsevier, Amsterdam, Netherlands, Earth and Planetary Science Letters, 302 (3-4), 279-286, georefid:2011-050053