| 976 / | HD | NUCLEAR TECHNOLOGY |
| DIG 403 | DD | RADIOACTIVE SOURCES [G21G-4/00] *** (producing neutrons or other subatomic particles, X- or gamma rays, in fusion reactors DIG. 1+, in nuclear reactors DIG. 5+; in accelerators H05H; X-ray tubes H01J-35/00; gamma masers H01S-4/00) {2} |
| DIG 405 | DD | .~ Radioactive sources other than neutron sources [G21G-4/04] {2} |
| DIG 406 | | .~.~ Characterized by constructional features [G21G-4/06] {1} |
| DIG 407 | DD | .~.~.~> Specially adapted for medical application [G21G-4/08] |