Bottke W., Vokrouhlický D., Nesvorný D. -LRB- 2007 -RRB- An asteroid breakup 160 Myr ago as the probable source of the K / T impactor.
Bottke WF, Vokrouhlický D Nesvorný D. -LRB- 2007 -RRB- An asteroid breakup 160 Myr ago as the probable source of the K / T impactor.