How to create PDF/A3 including XML file

I used PDF-Creator com object to create PDF file.
And I saw feature in PDF creator 4.4.1 supporting PDF/A3 but I cannot find any document or sample to attach XML and certificate file.
Please advice where to get sample or help file.

Thank you and regards,

Hi Pitak,

Sorry, for the long wait.

Could you please explain in detail how you want to have the XML and certificate file attached / included within PDF/A3? Could this be attached as last page?