Diana Ross and Marvin Gaye recorded a duets album called Diana & Marvin released as Motown M803 on October 26, 1973, according to the liner notes for the 2001 CD reissue.
It contained the following covers:
--"Don't Knock My Love", written by Wilson Pickett and Brad Shapiro, a hit for Wilson Pickett on Atlantic in 1971. Added in the meantime
--"Pledging My Love", written by Don D. Robey and Fats Washington, and according to the liner notes, a cover of Johnny Ace's hit, already in database at Pledging My Love Added in the meantime
--"You Are Everything", written by Bell/Creed, original already in database at You Are Everything Added in the meantime
--"Stop, Look, Listen (To Your Heart)", written by Bell/Creed, original already in database at Stop, Look, Listen (To Your Heart) Added in the meantime
On the 2001 CD reissue of "Diana & Marvin" (Motown 012 157 173-2), there are included a couple of bonus tracks that are covers:
--"The Things I Will Not Miss", written by Bacharach/David, is discussed in the liner notes as being a cover of a song from Bacharach & David's movie musical "Lost Horizon". According to http://www.imdb.com/title/tt0070337/soundtrack , the soundtrack/movie was released in 1973, and the song was performed in the movie and on the soundtrack by Sally Kellerman and Olivia Hussey (as dubbed vocally by Andra Willis). The Diana/Marvin release was unissued until 2001.
--"I'll Keep My Light In My Window", written by Leonard Caston & Terri McFadden, is a bonus cut on this CD reissue, but was previously released, according to liner notes, on the Various Artists LP, "Pops, We Love You...The Album", Motown M921, April 1979. Liner notes list the song as a cover version of Caston & Majors. Ebay listings confirm "Caston & Majors" as Motown M6-81451 in 1974 and show the song as "I'll Keep A Light In My Window" ("a" light vs. "my" light). Added in the meantime