Cita APA (7th ed.)

Hahn, D. B., Payne, W. A., & Mauer, E. (2009). Focus on health (9th ed.). McGraw-Hill.

Cita Chicago (17th ed.)

Hahn, Dale B., Wayne A. Payne, i Ellen Mauer. Focus on Health. 9th ed. Boston: McGraw-Hill, 2009.

Cita MLA (9th ed.)

Hahn, Dale B., et al. Focus on Health. 9th ed. McGraw-Hill, 2009.