N:
NRC: Byproduct Materials - Regulations, materials, and control measures for nuclear byproduct materials [Ad Hoc Organizations, Nuclear Regulatory Commission (NRC)]

NRC: Full-Text Glossary - Nuclear Energy Glossary [Ad Hoc Organizations, Nuclear Regulatory Commission (NRC)]

R:
Record Group 138: Records of the Federal Energy Regulatory Commission, 1917 - 2002 - National Archives' Archival Research Catalog description for Record Group 138: Records of the Federal Energy Regulatory Commission, 1917 - 2002 [National Archives and Records Administration (NARA)]

Record Group 431: Records of the Nuclear Regulatory Commission, 1967 - 1990 - National Archives' Archival Research Catalog description for Record Group 431: Records of the Nuclear Regulatory Commission, 1967 - 1990 [National Archives and Records Administration (NARA)]

Record Group 433: Records of the Mine Safety and Health Administration, 1911 - 2001 - National Archives' Archival Research Catalog description for Record Group 433: Records of the Mine Safety and Health Administration, 1911 - 2001 [National Archives and Records Administration (NARA)]