Deleting Links

Hi -

I went to this website http://workday.yale.edu/workday-core-concepts and removed the Cost Center bullet from the list because the information was out of date.

Then the owner of another site told me they were linking to the Cost Center file from their site: http://workday.yale.edu/sites/default/files/files/Cost%20Center(1).pdf

I know I can delete the file from the server, but is seems as though I went about this task the wrong way. Should I have broken the link before I deleted the bullet?  

What is the best way for me to remove an item from the Core Concepts to be sure I break any links other websites may have set up if I don’t want the displaying incorrect information?

Thanks.

-Kathi