Joe Biden’s presidential campaign is fixing his climate policy plan because a handful of passages did not credit some of the sources in the proposal.

The changes on Tuesday come after The Daily Caller reported that several passages from Biden’s plan appeared to borrow from policy papers written by outside groups without citation.

A campaign statement says, “Several citations, some from sources cited in other parts of the plan, were inadvertently left out of the final version of the 22-page document.”

Former vice president and Democratic presidential candidate Joe Biden speaks during a campaign event, Tuesday, June 4, 2019, in Berlin, N.H. (AP Photo/Elise Amendola)
Former vice president and Democratic presidential candidate Joe Biden speaks during a campaign event, Tuesday, June 4, 2019, in Berlin, N.H. (AP Photo/Elise Amendola)

The added citations included passages from documents published by the Blue Green Alliance and the Carbon Capture Coalition. The document by Biden, a former vice president under Barack Obama, cites sources in the text of the plan. Some other campaigns use more formal footnotes in their policy papers.

Biden’s 1988 presidential campaign ended amid controversy over plagiarized passages in his campaign speech and after he admitted plagiarism on a law school paper. At the time, Biden said the incident at Syracuse University was a matter of him not knowing the proper way to document sources.

President Donald Trump’s reelection campaign raised comments.

“Four decades in public life and there’s always one constant. What would a Joe Biden candidacy be without a little plagiarism?” said Tim Murtaugh, the campaign communications director.