Prominent New Zealand author Witi Ihimaera says he is deeply sorry for inadvertently using other authors' material without acknowledgment in his new novel.
The author, who is Professor of English and Distinguished Creative Fellow in Maori Literature at the University of Auckland, says some lines and paragraphs in his 528-page The Trowenna Sea were not credited.
In a written apology, Professor Ihimaera says he has been working with his publisher to contact authors whose work he did not acknowledge to express his regret and apologise for the oversight.
He says the passages in question will be fully acknowledged in a future edition of the book.
The university says it has investigated the matter and is satisfied there was no deliberate wrongdoing.
Penguin New Zealand says it will not be withdrawing the novel from the market.
Publishing director Geoff Walker says all of the authors involved will be fully recognised in future editions of the book. He says most of them have been contacted and have accepted the apologies offered.