(2000). Soil samplingtechnical engineering and design guides as adapted from the US Army Corps of Engineers, No. 30. ASCE.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Soil Samplingtechnical Engineering and Design Guides as Adapted from the US Army Corps of Engineers, No. 30. ASCE, 2000.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Soil Samplingtechnical Engineering and Design Guides as Adapted from the US Army Corps of Engineers, No. 30. ASCE, 2000.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.