Cita APA (7th ed.)

Lougheed, L. (2006). Barron's IELTS (International English Language Testing System). Barron's.

Cita Chicago (17th ed.)

Lougheed, Lin. Barron's IELTS (International English Language Testing System). Hauppauge, N.Y: Barron's, 2006.

Cita MLA (9th ed.)

Lougheed, Lin. Barron's IELTS (International English Language Testing System). Barron's, 2006.