- This Recommendation | International Standard is an integral part of the ODP Reference Model. It contains a formalisation of the ODP modeling concepts defined in ITU-T Rec. X.902 - ISO/IEC 10746-2, clauses 8 and 9. The formalisation is achieved by interpreting each concept in terms of the constructs of the different standardised formal description techniques. This Recommendation | International Standard is accompanied by an amendment and a technical report. The associated amendment focuses on the formalisation of the computational viewpoint language contained n ITU-T Rec. X.903 | ISO/IEC 10746-3. The associated technical report contains examples on how the formalisation of the ODP Reference Model can be applied to develop specifications.