1. United States Pharmacopeial Convention. Microbial limit test. In U.S. Pharmacopoeia. Rockville, Maryland:United States Pharmacopeial Convention, 2002:1873-1878.
2. Federal Register of the United States of America. Code of Federal Regulations. Subpart F: Production and Process Control, 21 Part 211.113: Control of microbiological contamination. Rockville, Maryland, 1996.