1. AOAC (2000) Official methods of analysis of AOAC international, official method 999.11: Gaithersburg, MD, USA
2. AOAC (2005a) Official methods of analysis of AOAC international, official method 955.04: Gaithersburg, MD, USA
3. AOAC (2005b) Official methods of analysis of AOAC international, official method 960.39: Gaithersburg, MD, USA
4. AOAC (2005c) Official methods of analysis of AOAC international, official method 923.03: Gaithersburg, MD, USA
5. AOAC (2005d) Official methods of analysis of AOAC international, official method 962.09: Gaithersburg, MD, USA