Washington, DC -- Art Garfunkel doesn't rule out another reunion with Paul Simon. He says "who knows what the future brings?" Garfunkel calls Simon his "old buddy" and the first friend he ever had. Garfunkel commented as Simon and Garfunkel's "Sounds of Silence" was added to the National Recording Registry. Twenty-four other recordings will also be preserved by the Library of Congress, including Pink Floyd's "Dark Side of the Moon." the Bee Gees album "Saturday Night Fever" and Chubby Checker's "The Twist."