Tammy Wynette's country classic Stand By Your Man and Al Green's soul hit Let's Stay Together have been selected for official preservation by the Library of Congress, sealing their status as national treasures in the U.S.
The two tracks are among 25 recordings added to the ninth annual National Recording Registry (Nrr) of the Library of Congress. Others include the theme from TV show Peter Gunn - made famous by Duane Eddy - and performances by Nat King Cole, Steely Dan, and De La Soul.
Also chosen for the honour - which marks recordings which are considered "culturally, historically or aesthetically significant" - are an unauthorised recording of a concert by comedian Mort Sahl and a sermon from Aretha Franklin's father, Baptist minister C.L. Franklin.
Announcing the latest additions to the Nrr, Librarian of Congress James H. Billington says, "Songs, words and the natural sounds of the world that we live in have been captured on one of the most perishable of all of our art media. The salient question is not whether we should preserve these artifacts, but how best collectively to save this indispensable part of our history."