Lookup Table:-the Hydraulic Equipmet document references 11 other documents.

Hi,

I'm wondering if anyone can help me with a clever way of looking up this table for me. I've been scratching my head for a couple of hours now. I've attached a JPEG to help explain what I am trying to do...

I have a list of documents listed down the page and then again beneath (the are the same set of documents). what I want to do is populate each of the boxes with a 'Y' (for yes) if the document along the bottom is referenced reference within the document along the side. eg. I have populated one row, the Hydraulic Equipmet document references 11 other documents.

Basically what I want to do is systemically lookup up each document running down the page and return a list of what documents are referenced within it.

Can anyone help?