Tax Report new Table add

Hi Everyone,

I am customizing standard Tax Report in E9. I need to add a UD field from APTran Table to the report.
I am not able to find any relation between TempTaxTran (Report view) and APTran. I have also tried adding TempTaxTran to TaxTran table. But here again no relationship I found.
Can anyone help on this?
Thanks in advance.