The role of functional objects 
Revision log
| Date | Revision description |
| 2022-10-09 | Added the sentence (in red) that states that instances of (ClassOf)FunctionalObject ARE "useful objects". |
| 2022-10-04 | Minor updates |
| 2021-04-21 | Minor corrections |
| 2017-07-09 | Due to the agreement on the semantics of ClassOfFunctionalObject the PUMP has moved to ClassOfFunctionalObject. |
| 2016-10-24 | Minor corrections |
| 2015-12-18 | Removed reference to ISO 15926-4 INANIMATE PHYSICAL OBJECT |
| 2015-10-21 | Added example |
| 015-06-21 | First issue |