Reference to other workbook

I am building an economic model, the input data (costs etc) is held as named ranges in one workbook, and the cash flow calculation are in an alternative workbook. I am using the =INDIRECT function to reference the input data based on cell values that define the file name, the desired sheet and the named range. It is a given that both files are kept within the same folder (same path). The Formula is

=INDIRECT("'["&HOME!$D$3&".xlsx]"&HOME!$D$4&"'!"&B8)

Where HOME!$D$3 = filename, HOME!$D$4 = Sheet name and B8 is the named range.

This works fine, BUT only when both files are open... If I close the input file the link is ok until I do something in the model ..then I get #REF!.. is there a way to keep the data without using a copy and paste values approach.

Any "nice" solution will be helpful ... thanks

"nice"... I suppose I mean simple.. without too many additional processes/functions... I'd like keep it here for the time being.. for a number of reasons I'm trying to avoid VBA at this point..

thanks