Prevent Excel file for linking to external files

We have an Excel file in use that several people in our company use as a source file. We have protected the sheet - where possible - from unwanted and unintentional changes. However, with some regularity, links to other Excel files arise when sharing the file. Probably because users need certain data and, instead of copying the data, inadvertently create a link to it. My question is whether there is any way to protect a workbook from creating external links?