Cita APA (7th ed.)

Hughes, P., & Ferrett, E. (2009). Introduction to health and safety at work: The handbook for the NEBOSH national general certificate (4th ed.). Elsevier.

Cita Chicago (17th ed.)

Hughes, Phil, i Ed Ferrett. Introduction to Health and Safety at Work: The Handbook for the NEBOSH National General Certificate. 4th ed. Amsterdam: Elsevier, 2009.

Cita MLA (9th ed.)

Hughes, Phil, i Ed Ferrett. Introduction to Health and Safety at Work: The Handbook for the NEBOSH National General Certificate. 4th ed. Elsevier, 2009.