Direct measurements of carbon and sulfur isotope ratios in the Milky Way Y. T. Yan, C. Henkel, C. Kobayashi, K. M. Menten, Y. Gong, J. S. Zhang, H. Z. Yu, K. Yang, J. J. Xie and Y. X. Wang A&A, 670 (2023) A98 Published online: 14 February 2023 DOI: 10.1051/0004-6361/202244584