How do you indicate in a business letter that copies of that same letter are being sent to other recipients?

At the bottom of the letter, below the senders name/title, below enclosures listed (if applicable), the notation 'Copy:' or 'Copies:' can replace the old fashioned 'Cc:' (carbon copy); for example:

Copy: Dr. Linda Likely

Copies: Dr. Linda Likely, Stephen Stephens, Roy Royal