VORKAPIĆ, S. T.; BABIĆ ŠIKIĆ, A. What Pre-school Children Think about Happiness, Hope, Gratitude, Wisdom, Justice, and Optimism? The Positive Conceptual Thinking Development Study. Journal of Positive School Psychology , [S. l.], v. 3, n. 1, p. 1-25, 2018. Disponível em: https://journalppw.com/index.php/JPPW/article/view/59. Acesso em: 3 mar. 2021.