KULVIECAS, L. One method to define the concepts of physical quantities of derivatives. Psichologija, [S. l.], v. 7, p. 77–85, 1965. DOI: 10.15388/Psichol.1965.7.8912. Disponível em: https://www.journals.vu.lt/psichologija/article/view/8912. Acesso em: 11 apr. 2025.