formula to get list of items from 1 col based on a criteria in another col

Hi,

I have 5 columns in a sheet like this
Doc_Ref--------Item_No-----TITLE------group-----ID_No
What I do is :I add Autofilter
Then filter Colum A that is Doc Ref: select the first Ref No:
Then copy all visible Item Nos and paste the same to a new file
Again I filter the 2nd Doc Ref, and then copy the respective Item Nos to a different file and so on

"Required output Is there any formula for getting all the Item Nos If I just enter the Doc Ref number in a cell and then should get all the Item numbers next to it

I have attached a sample file for reference

Cross post is here : http://www.mrexcel.com/forum/showthr...73#post2166273