Gilbert MT, Jenkins DL, Götherstrom A, Naveran N, Sanchez JJ, Hofreiter M, et al. (mai 2008). «DNA from pre-Clovis human coprolites in Oregon, North America». Science320 (5877): 786–9. Bibcode:2008Sci...320..786G. PMID18388261. doi:10.1126/science.1154116.
Poinar H, Fiedel S, King CE, Devault AM, Bos K, Kuch M, Debruyne R (juli 2009). «Comment on "DNA from pre-Clovis human coprolites in Oregon, North America"». Science325 (5937): 148; author reply 148. Bibcode:2009Sci...325..148P. PMID19589985. doi:10.1126/science.1168182.
Gilbert MT, Jenkins DL, Götherstrom A, Naveran N, Sanchez JJ, Hofreiter M, et al. (mai 2008). «DNA from pre-Clovis human coprolites in Oregon, North America». Science320 (5877): 786–9. Bibcode:2008Sci...320..786G. PMID18388261. doi:10.1126/science.1154116.
Poinar H, Fiedel S, King CE, Devault AM, Bos K, Kuch M, Debruyne R (juli 2009). «Comment on "DNA from pre-Clovis human coprolites in Oregon, North America"». Science325 (5937): 148; author reply 148. Bibcode:2009Sci...325..148P. PMID19589985. doi:10.1126/science.1168182.
Gilbert MT, Jenkins DL, Götherstrom A, Naveran N, Sanchez JJ, Hofreiter M, et al. (mai 2008). «DNA from pre-Clovis human coprolites in Oregon, North America». Science320 (5877): 786–9. Bibcode:2008Sci...320..786G. PMID18388261. doi:10.1126/science.1154116.
Poinar H, Fiedel S, King CE, Devault AM, Bos K, Kuch M, Debruyne R (juli 2009). «Comment on "DNA from pre-Clovis human coprolites in Oregon, North America"». Science325 (5937): 148; author reply 148. Bibcode:2009Sci...325..148P. PMID19589985. doi:10.1126/science.1168182.