RT Journal Article SR Electronic T1 Initial combination therapy of macitentan and tadalafil in pulmonary arterial hypertension JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP 2000673 DO 10.1183/13993003.00673-2020 VO 56 IS 3 A1 Olivier Sitbon A1 Vincent Cottin A1 Matthieu Canuet A1 Pierre Clerson A1 Virginie Gressin A1 Loïc Perchenet A1 Laurent Bertoletti A1 Hélène Bouvaist A1 François Picard A1 Grégoire Prévot A1 Emmanuel Bergot A1 Gérald Simonneau YR 2020 UL http://erj.ersjournals.com/content/56/3/2000673.abstract AB