The ALMA Redshift 4 Survey (AR4S) - I. The massive end of the z = 4 main sequence of galaxies C. Schreiber, M. Pannella, R. Leiton, D. Elbaz, T. Wang, K. Okumura and I. Labbé A&A, 599 (2017) A134 Published online: 14 March 2017 DOI: 10.1051/0004-6361/201629155