Hellawell, J. M. (1986). Biological indicators of freshwater pollution and environmental management. Elsevier Applied Science Publishers.
استشهاد بنمط شيكاغوHellawell, J. M. Biological Indicators of Freshwater Pollution and Environmental Management. Elsevier Applied Science Publishers, 1986.
MLA استشهادHellawell, J. M. Biological Indicators of Freshwater Pollution and Environmental Management. Elsevier Applied Science Publishers, 1986.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.