“ After any unit is cited pursuant to paragraph 1 hereof for outstanding performance in action, a ribbon identifying such citation shall be issued and shall become a permanent part of the uniform of those persons assigned or attached thereto who were actually present and participated in the action for which they are eligible, made either to the same unit or to a unit to which they are subsequently assigned. If authorized by the Secretary concerned, persons assigned to a unit subsequent to an action for which it was cited, may wear the citation ribbon while so assigned. ”