2. Classify basic scientific research information that is not clearly related to the national security.
3. Classify, or use as a basis for classification, references to classified documents, when the reference citation does not itself disclose classified information.
1. SECNAVINST 5216.5C, Department of the Navy Correspondence Manual
2. SECNAVINST 5210.11C, Navy Standard Subject Identification Codes
3. OPNAVINST 5510.1G, Navy Information Security Program Regulation
4. AP Pamphlet 13-5, US Air Force Effective Writing Course, 1980