Dalrymple, G. Brent (2001). "The age of the Earth in the twentieth century: a problem (mostly) solved". Special Publications, Geological Society of London. 190 (1): 205–221. डीओआइ:10.1144/GSL.SP.2001.190.01.14. बिबकोड:2001GSLSP.190..205D.
Bowring, Samuel A.; Williams, Ian S. (1999). "Priscoan (4.00–4.03 Ga) orthogneisses from northwestern Canada". Contributions to Mineralogy and Petrology. 134 (1): 3. डीओआइ:10.1007/s004100050465. बिबकोड:1999CoMP..134....3B. The oldest rock on Earth is the Acasta Gneiss, and it dates to 4.03 Ga, located in the Northwest Territories of Canada.
harvard.edu
ui.adsabs.harvard.edu
Dalrymple, G. Brent (2001). "The age of the Earth in the twentieth century: a problem (mostly) solved". Special Publications, Geological Society of London. 190 (1): 205–221. डीओआइ:10.1144/GSL.SP.2001.190.01.14. बिबकोड:2001GSLSP.190..205D.
Bowring, Samuel A.; Williams, Ian S. (1999). "Priscoan (4.00–4.03 Ga) orthogneisses from northwestern Canada". Contributions to Mineralogy and Petrology. 134 (1): 3. डीओआइ:10.1007/s004100050465. बिबकोड:1999CoMP..134....3B. The oldest rock on Earth is the Acasta Gneiss, and it dates to 4.03 Ga, located in the Northwest Territories of Canada.
Historically, the Cenozoic has been divided up into the Quaternary and Tertiary sub-eras, as well as the Neogene and Paleogene periods. The 2009 version of the ICS time chart recognizes a slightly extended Quaternary as well as the Paleogene and a truncated Neogene, the Tertiary having been demoted to informal status.
ucsb.edu
flatpebble.nceas.ucsb.edu
Paleontologists often refer to faunal stages rather than geologic (geological) periods. The stage nomenclature is quite complex. For an excellent time-ordered list of faunal stages, see "The Paleobiology Database". अभिगमन तिथि 2006-03-19.
usgs.gov
pubs.usgs.gov
"Age of the Earth". U.S. Geological Survey. 1997. मूल से 23 दिसंबर 2005 को पुरालेखित. अभिगमन तिथि 2006-01-10.
web.archive.org
"Age of the Earth". U.S. Geological Survey. 1997. मूल से 23 दिसंबर 2005 को पुरालेखित. अभिगमन तिथि 2006-01-10.