Introduction: Most albums come with a sleeve that often contain liner notes; usually a message
of some sorts from the band or information on the album, song lyrics, etc. In the case of Nirvana,
the liner notes to Nevermind came in the form of lyrics snippets and fragments from Kurt's poetry.
With some copies of Incesticide, an angry message from Kurt comprised the liner notes instead.
You can find liner notes for most of Nirvana's albums here as well as a selection of liner notes from miscellanous tribute albums.
From The Muddy Banks of the Wishkah
Sliver: The Best of the Box (thanks to Christian)
War Help compilation
Smells Like Bleach
A Tribute to Nirvana