Debruyne, R., Chu, G., King, C. E., Bos, K., Kuch, M., Schwarz, C., et al. (2008). Out of America: Ancient DNA evidence for a new world origin of late quaternary woolly mammoths. Current Biology, 18(17), 1320-1326. doi:10.1016/j.cub.2008.07.061.