ericstaytrue,
Thank you for your suggestion – it worked!
There was indeed what appeared to be a single character in the URL line between the slash and the following character. By carefully arrowing over each occurrence (in the WP text editor mode) and back-spacing over the invisible character I was able to get rid of them.
While I’m very grateful for the help, I am wondering what I can do (or NOT do) to avoid having to use this remedy in the future. Is it a symptom of pasting to and then copying from a text editor outside of WordPress that is introducing these weird characters? Perhaps a discrepancy between the character sets of the text editor and WordPress? I guess I’ll have to experiment…
Thanks again,
Jonathan