BERNOTAS , V. A. Gerd – the initiator of the investigation principle in the methods of teaching of natural sciences. Psichologija, [S. l.], v. 12, p. 169–176, 1972. DOI: 10.15388/Psichol.1972.12.9275. Disponível em: https://test.zurnalai.vu.lt/psichologija/article/view/9275. Acesso em: 26 oct. 2025.