JUOZAPAVIČIUS, A. Research Information Systems. Nonlinear Analysis: Modelling and Control, [S. l.], v. 1, n. 1, p. 29–37, 1997. DOI: 10.15388/NA.1997.1.0.15267. Disponível em: https://www.zurnalai.vu.lt/nonlinear-analysis/article/view/15267. Acesso em: 20 apr. 2025.