reference one repository into another in Subversion

1. In TortoiseSVN's Repo-browser, right-click on a folder to bring references into and and pick "Show properties"
2. "New..." button at far-right of "Properties" pane
3. "Other" should allow you to make a new Property here, but if you pick an existing Property and pick "New..." at the dialog which appears a third dialog box yet will appear
4. put an SVN path in the URL property and in "Local path" put the name of you pseduofolder to be
5. start OKing out of the dialogs to save your alteration
6. do an Update (pull down the files from the external source)
7. do a commit (commit the programmatic change of referencing the external stuff)
8. refresh the folder holding reference within the Repo-browser