MUIR, Jr. JR. Linear invariance and extension operators of Pfaltzgraff–Suffridge type. Stud. Univ. Babeş-Bolyai Math. [Internet]. 2022 Jun. 10 [cited 2025 Jul. 14];67(2):295–308. Available from: https://studia.reviste.ubbcluj.ro/index.php/subbmathematica/article/view/1484