Hughes, P., & Ferrett, E. (2009). Introduction to health and safety at work: The handbook for the NEBOSH national general certificate (4th ed.). Butterworth-Heinemann.
استشهاد بنمط شيكاغوHughes, Phil, و Ed Ferrett. Introduction to Health and Safety at Work: The Handbook for the NEBOSH National General Certificate. 4th ed. Burlington: Butterworth-Heinemann, 2009.
MLA استشهادHughes, Phil, و Ed Ferrett. Introduction to Health and Safety at Work: The Handbook for the NEBOSH National General Certificate. 4th ed. Butterworth-Heinemann, 2009.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.