1. Pearson’s Composition and Analysis of Foods;Kirk,1989
2. Milk and milk products – determination of nitrate and nitrite contents – Part 1: Method using cadmium reduction and spectrometry,2001
3. AOAC Official Method 935.48. Nitrates and nitrites in meat, xylenol method,2000
4. AOAC Official Method 973.31. Nitrites in cured meat, colorimetric method. Codex-Adopted-AOAC Method,2000
5. AOAC Official Method 976.14. Nitrate and nitrite in cheese, modified Jones reduction method,2000