* NASA's Orbiting Carbon Observatory* The on-line catalogue of CO2 natural emissions in Italy* Reactions, Thermochemistry, Uses, and Function of Carbon Dioxide* Carbon Dioxide – Part One and Carbon Dioxide – Part Two at "The Periodic Table of Videos" (University of Nottingham)
* NASA's Orbiting Carbon Observatory* The on-line catalogue of CO2 natural emissions in Italy* Reactions, Thermochemistry, Uses, and Function of Carbon Dioxide* Carbon Dioxide – Part One and Carbon Dioxide – Part Two at "The Periodic Table of Videos" (University of Nottingham)