2019SY/T 5238-2019 Methods for analyzing carbon and oxygen isotopes of organic matter and carbonate rocks
2008SY/T 5238-2008 Analysis method for carbon and oxygen isotope in organic matter and carbonate
1991SY/T 5239-1991 Methods for Hydrogen and Carbon Isotope Analysis of Petroleum and Sedimentary Organic Matter
SY/T 5239-1991 Methods for Hydrogen and Carbon Isotope Analysis of Petroleum and Sedimentary Organic Matter was changed to SY/T 5238-2008 Analysis method for carbon and oxygen isotope in organic matter and carbonate.