A new expanded paperback edition of Kurt Cobain's "Journals" has an added 14 pages of bonus material, including an extended narrative about a semi-fictional serial killer, Billboard reports.

"Frankly, we had this the first time around but we chose not to include it because it's disturbing and bizarre," said Julie Grau, co-editorial director of Riverhead Books. "I think the first time, we thought it would skew the appreciation of all the material that was in here.

"Now that the hardcover has come out and the journals have been judged and read, we though people could handle it."

Grau said the narrative contained characteristics and biographic facts that described a known serial killer, but it was hard to know what was real and what Cobain had invented.

Also included in the bonus pages are lyrics to an unrecorded song titled "Travelin' White Trash Couple," a cookie recipe and a previously unpublished list of Cobain's favourite albums. Cobain's widow, singer Courtney Love, recently uncovered some of the material while moving.

Despite the initial controversy that arose when plans were made to publish the journals of the late Nirvana frontman, the hardcover edition of the journal became an instant number one best-seller when it was released earlier this fall.

"Time doesn't seem to diminish interest in Kurt or his icon status," said Grau.