Cita APA (7th ed.)

Abbs, B., & Freebairn, I. (1994). Blueprint one.: Students` book (1a. ed. 6a. imp.). Longman.

Cita Chicago (17th ed.)

Abbs, Brian, i Ingrid Freebairn. Blueprint One.: Students` Book. 1a. ed. 6a. imp. Madrid: Longman, 1994.

Cita MLA (9th ed.)

Abbs, Brian, i Ingrid Freebairn. Blueprint One.: Students` Book. 1a. ed. 6a. imp. Longman, 1994.