global update to references in library

I have hundreds of references in my library. I need to update the page field in most of them, specifically by replacing “space hyphen space” in the page range with “no space emdash no space”. Is there an automated approach available to do this, e.g. by use of a global find/replace function, or must it be done manually one record at a time? TIA … Greg

I have copied the emdash from word and then performed a replace on the pages field - and copied the emdash from word to endnote.  I has worked in the past.  however I know that publishers will fix this  kind of issue with their house style tools.