1. Determination of milk urea by flow injection analysis;Andersson;J. Vet. Med. Series A.,1986
2. Appendix D: Guidelines for collaborative study procedures to validate characteristics of a method of analysis. Official Methods of Analysis of AOAC International;AOAC International,2019
3. Appendix F: Guidelines for standard method performance requirements. Official Methods of Analysis of AOAC International;AOAC International,2019
4. Official Methods of Analysis;AOAC International,2019
5. Comparison of Babcock and ether extraction methods for determination of fat content of milk: Collaborative study;Barbano;J. Assoc. Off. Anal. Chem.,1988