The Digital NOTAM Specification defines the rules for harmonised encoding of NOTAM information as digital AIXM data sets (version 5.1 or later).
Version
2.0
Conformance Statement
The service conforms with the standard as per Technical Constraints section of the current service description.
Reference
https://ext.eurocontrol.int/aixm_confluence/display/DNOTAM/Digital+NOTAM+Specification