Merrill, C. W., Henderson, C. W., & Kiessling, O. E. (1937). Small-scale placer mines as a source of gold, employment, and livelihood in 1935. Works Progress Administration, National Research Project on Reemployment Opportunities and Recent Changes in Industrial Techniques.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Merrill, Charles W., Charles W. Henderson, و O. E. Kiessling. Small-scale Placer Mines as a Source of Gold, Employment, and Livelihood in 1935. Philadelphia: Works Progress Administration, National Research Project on Reemployment Opportunities and Recent Changes in Industrial Techniques, 1937.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Merrill, Charles W., et al. Small-scale Placer Mines as a Source of Gold, Employment, and Livelihood in 1935. Works Progress Administration, National Research Project on Reemployment Opportunities and Recent Changes in Industrial Techniques, 1937.