| Assumptions | Proposed solutions | References |
| The implementation can have extra states | Bounded number of extra states | [40] |
| Time | Test boundaries (maximum duration of a timer) | [41] |
| Variables within a range | Domain testing and/or boundary testing | [42] |
| Variables within a range | Symbolic approaches | [43] - [45] |
| Partial specifications | Verifying partial inclusion: | [46] |
| Partial specifications | Inferring partial models | [47] |