| 423 / | HD | CHEMISTRY OF INORGANIC COMPOUNDS |
| 276 | DF | BORON OR COMPOUND THEREOF {5} |
| 277 | DF | .~ Oxygen containing {3} |
| 279 | DF | .~.~ Ternary compound containing metal or ammonium {1} |
| 280 | DF | .~.~.~ Utilizing dissolved or liquid reactant {2} |
| 281 | | .~.~.~.~ Peroxide |