Beerling D.J.; Lake J.A.; Berner R.A.; Hickey L.J.; Taylor D.W.; Royer D.L.(2002)
Theoretical models predict a marked increase in atmospheric O2 to ~35% during the Permo-Carboniferous (~300 Ma) occurring against a low (~0.03%) CO2 level. An upper O2 value of 35%, however, remains disputed because ignition ...