Here are some facts about "D-7" from Wikipedia :
"D-7" is a song originally performed by The Wipers appearing on their 1980 album "Is This Real?" and is most popularly known for the Nirvana version appearing on their 1992 EP "Hormoaning" and also on the box set "With The Lights Outs".
The song Return of the Rat off the same album (Is This Real?) has also been covered by Nirvana also appearing on the box set "With The Lights Outs".