Citazione Stile APA (7a Edizione)

Hitt Espinosa, F. A., & Santos, M. (1999). Proceedings of the twenty first annual meeting: Psychology of mathematics education PME-NA XXI. ERIC.

Citazione stile Chigago Style (17a edizione)

Hitt Espinosa, Fernando Antonio, e Manuel Santos. Proceedings of the Twenty First Annual Meeting: Psychology of Mathematics Education PME-NA XXI. Columbus: ERIC, 1999.

Citatione MLA (9a ed.)

Hitt Espinosa, Fernando Antonio, e Manuel Santos. Proceedings of the Twenty First Annual Meeting: Psychology of Mathematics Education PME-NA XXI. ERIC, 1999.