PROSKURIN, D. P. About positivity of Fock inner product of a certain Wick algebras. Methods of Functional Analysis and Topology, [S. l.], v. 5, n. 1, p. 88–94, 1999. Disponível em: https://zen.imath.kiev.ua/index.php/mfat/article/view/82. Acesso em: 17 dec. 2025.