SEARCH Articles Figures Tables Isotope dilution Isotope dilution spectrometry Isotope dilution thermal ionization mass spectrometry Isotope spectrometry Isotope-dilution mass spectrometry Isotopes masses Isotopic dilution Isotopic mass spectrometry Isotopic masses Mass isotope dilution Mass spectrometry ionization Mass spectrometry ionized Mass spectrometry isotopes Thermal ionization Thermal ionization mass Thermal ionization mass spectrometry Thermal ionization mass spectrometry TIMS) Thermal spectrometry