Relationship between 109 MVT document number for a perticular 107 document

Hi Guru's

We need to fetch some details from the material document which are generated for the MVT 107 and 109. We need to fetch GR date from 107 document and un restricted quanity from 109 document. but there is aa issue to find the right relation between this documents. Developers questine is that, How the system will find the right 109 document against the perticualr 107 document. Please advise the table or relationship which connect these two document.

Thanks

Regards

Raja