ALMA observations of the Extended Green Object G19.01-0.03 - I. A Keplerian disc in a massive protostellar system

masers, techniquesinterferometric, starsformation, starsindividualG19.01-0.03, starsmassive, starsprotostars, Astrophysics - Astrophysics of Galaxies, Astrophysics - Solar and Stellar Astrophysics