Updated orbital ephemeris of the ADC source X 1822-371: a stable orbital expansion over 40 years S. M. Mazzola, R. Iaria, T. Di Salvo, A. F. Gambino, A. Marino, L. Burderi, A. Sanna, A. Riggio and M. Tailo A&A, 625 (2019) L12 Published online: 20 May 2019 DOI: 10.1051/0004-6361/201935665