VAN DELFT, Dirk. Einsteins Hollandse cirkel. Studium, Amsterdam, v. 9, n. 1-2, p. 1–5, 2016. DOI: 10.18352/studium.10124. Disponível em: https://platform.openjournals.nl/studium/article/view/20379.. Acesso em: 22 dec. 2024.