LAUŽIKAS, J. On the development of volitional activity in mentally deficient pupils. Psichologija, [S. l.], v. 9, n. 1, p. 33–46, 1968. DOI: 10.15388/Psichol.1968.9.8917. Disponível em: https://www.journals.vu.lt/psichologija/article/view/8917. Acesso em: 6 dec. 2025.