Celebrated Reagan biographer Craig Shirley said Wednesday that he will file a suit against Simon & Schuster, the publisher of a new book about the Gipper that Shirley claims ripped off whole sections of his 2004 “Reagan’s Revolution: The Untold Story of the Campaign that Started It All.”

Shirley told Secrets that the suit may be filed as early as next week. It will demand a public apology and a reprinting of Rick Perlstein’s “Invisible Bridge: The Fall of Nixon and the Rise of Reagan,” that includes proper citations for his work.

“We are suing. I am definitely going to have a lawsuit,” said Shirley, also the author of “Rendezvous With Destiny: Ronald Reagan and the Campaign That Changed America.”

“My terms are not negotiable,” added Shirley, who conducted 104 interviews for his Reagan book, some of which he claims Perlstein cribbed without proper attribution. In a recent letter to Simon & Schuster, he suggested a damages amount of $25 million, but that could change when the suit is filed.

Shirley, the head of the conservative public relations firm Shirley & Banister, has found at least 45 instances of his reporting and scholarship taken by Perlstein and not attributed in “Invisible Bridge.”

Perlstein, appearing on MSNBC’s “Morning Joe” show Wednesday, claimed however that the passages “are not the same,” and suggested his similar descriptions of Reagan were “richer” than Shirley’s.

“I thought I was friends with him,” said Perlstein. “He wants my book pulped, shredded. I want his book read.”

He also said that Shirley was “ideologically motivated” against him because his book is critical of Reagan, but Shirley said he simply wants Perlstein to act like a historian and cite sources in his book.

Since the fight went public, Shirley has received hate mail from those who don’t like Reagan and cheer the anti-Reagan theme some reviewers have cited in Perlstein’s book. One emailed: “Anything that harms Reagan or makes a Reagan backer look like a nitwit is a good thing.”

Typically biographies include citations and other references to works of others used by authors. Perlstein instead puts some of those references on his website, which is not part of Simon & Schuster, and isn't expected to have the shelf life of notes in the back of a book. He lists dozens of references to Shirley and his book on the website.

That unusual arrangement violates tradition and rules on plagiarism which demand that source notes be in historical books, said Shirley. His lawsuit is likely to note similar cases of plagiarism against Simon & Schuster biographers Stephen Ambrose and Doris Kearns Goodwin. That could make the publisher vulnerable in the new suit.

In fact, the Atlantic magazine said Perlstein has shown in his latest political history that he is less a researcher-historian than a simple “web aggregator” who collects publicly available information and stitches it into a book.

Simon & Schuster spokesperson Cary Goldstein responded: "We are not aware of any lawsuit. As we have said before, we have examined Mr. Shirley’s claims, found them to be entirely without merit, and responded to him accordingly. In 'The Invisible Bridge,' Rick Perlstein, an acclaimed and award-winning historian and author, has written an 800-plus page masterwork that draws upon hundreds of sources, all of which are amply credited in more than 4000 citations. Making this claim even more absurd, these citations are readily available for one and all to see on Mr. Perlstein’s website, where Shirley’s work alone is credited more than 100 times, and with links to the relevant passages where available."

Paul Bedard, the Washington Examiner's "Washington Secrets" columnist, can be contacted at pbedard@washingtonexaminer.com.