| 208 / | HD | MINERAL OILS: PROCESSES AND PRODUCTS |
| 177 | DF | REFINING {23} |
| 189 | DF | .~ Sweetening {6} |
| 197 | DF | .~.~ With lead compounds {2} |
| 199 | | .~.~.~ Sodium plumbite {2} |
| 200 | DF | .~.~.~.~> With preliminary treatment of the oil |
| 201 | DF | .~.~.~.~> With subsequent treatment of the sweet oil {1} |