Accommodating the freedom of online platforms to provide services through the incidental direct effect back door: Case C-390/18,X, YA, Airbnb Ireland UC, Hôtelière Turenne SAS, Association pour un hébergement et un tourisme professionnels (AHTOP), Valhotel, Judgment of the Court (Grand Chamber) of 19 December 2019, EU:C:2019:1l12
