BERRY, John; FENTEM, Roger; PARTANEN, Anna-Maija; TIIHALA, Sirkka. The use of symbolic algebra in learning mathematics: the barrier from formal examination schemes. NOMAD Nordic Studies in Mathematics Education, [S. l.], v. 9, n. 4, p. 49–64, 2004. DOI: 10.7146/nomad.v9i4.147151. Disponível em: https://tidsskrift.dk/NOMAD/article/view/147151. Acesso em: 7 dec. 2025.