Geologic Time Scale 2020Felix M. Gradstein, James G. Ogg, Mark Schmitz, Gabi Ogg · First published 2020Open the Tome
Concise Geologic Time Scale 2016James G. Ogg, Gabi Ogg, Felix M. Gradstein · First published 2016Open the Tome
Geologic Time Scale 2004Felix M. Gradstein, James G. Ogg, A. Gilbert Smith · First published 2004 · Latest edition 2005Open the Tome
