Each SESSION
| K | must be delivered at one and only one CLINIC OR FACILITY |
| K | must be located at one and only one LOCATION |
| K | or must be located at one and only one OPERATING THEATRE |
| K | or must be located at one and only one ORGANISATION SITE |
| may be the context of one or more ACTIVITY | |
| may be divided into one or more APPOINTMENT SLOT | |
| may be classified by one and only one TREATMENT FUNCTION |