Optimization of on-line hydrogen stable isotope ratio measurements of halogen- and sulfur-bearing organic compounds using elemental analyzer–chromium/high-temperature conversion isotope ratio mass spectrometry (EA-Cr/HTC-IRMS) - Gehre, Matthias; Renpenning, Julian; Geilmann, Heike; Qi, Haiping; Coplen, Tyler; Kummel, Steffen; Ivdra, Natalija; Brand, Willi; Schimmelmann, Arndt (Rapid Communications in Mass Spectrometry, 2017)