ROTH, Oliver. “The Nehari–Schwarz Lemma and Infinitesimal Boundary Rigidity of Bounded Holomorphic Functions”. Studia Universitatis Babeș-Bolyai Mathematica 67, no. 2 (June 10, 2022): 285–294. Accessed February 5, 2025. https://studia.reviste.ubbcluj.ro/index.php/subbmathematica/article/view/1482.