Bick, H. (1972). Ciliated protozoa: An illustrated guide to the species used as biological indicators in freshwater biology. World Health Organization.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Bick, Hartmut. Ciliated Protozoa: An Illustrated Guide to the Species Used as Biological Indicators in Freshwater Biology. Geneva: World Health Organization, 1972.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Bick, Hartmut. Ciliated Protozoa: An Illustrated Guide to the Species Used as Biological Indicators in Freshwater Biology. World Health Organization, 1972.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.