First detection of H2S in a protoplanetary disk - The dense GG Tauri A ring N. T. Phuong, E. Chapillon, L. Majumdar, A. Dutrey, S. Guilloteau, V. Piétu, V. Wakelam, P. N. Diep, Y.-W. Tang, T. Beck and J. Bary A&A, 616 (2018) L5 Published online: 15 August 2018 DOI: 10.1051/0004-6361/201833766