How does pump P-101 fit in? 
Revision log
| Date | Revision description |
| 2024-10-27 | Editorial changes |
| 2024-08-13 | Extended not about metaclasses with their role in defining RDL Classes |
| 2024-05-03 | Updated the added two diagrams |
| 2024-04-24 | Added an explanation below the added two diagrams |
| 2024-04-21 | Added two diagrams |
| 2021-01-11 | Editorial changes |
| 2019-11-09 | Editorial changes, replaced links to other topics |
| 2018-12-22 | Removed FunctionalPhysicalObject and MaterializedPhysicalObject |
| 2018-01-14 | Updated to account for new subtypes of PossibleIndividual and PhysicalObject (lci:...) |
| 2017-06-19 | Adapted to agreed-upon semantics of ClassOfFunctionalObject; removed code |
| 2015-03-01 | Extended the diagram |
| 2015-02-15 | First issue |