NICOLA, F. On the absence of the one-sided Poincaré lemma in Cauchy-Riemann manifolds. ANNALI SCUOLA NORMALE SUPERIORE - CLASSE DI SCIENZE, [S. l.], v. 4, n. 4, p. 587-600, 2009. DOI: 10.2422/2036-2145.2005.4.02. Disponível em: https://journals.sns.it/index.php/annaliscienze/article/view/80. Acesso em: 20 feb. 2026.