AUSTIN, April 7 -- In one of the largest such purchases in American history, the University of Texas at Austin has bought the Watergate papers of Bob Woodward and Carl Bernstein for $5 million, the university announced today.

The archive -- 75 file-drawer-size boxes of notebooks, memos, correspondence, photographs, clippings, manuscripts, transcriptions and loose notes from the authors’ reporting for The Washington Post and for their two books on the Nixon administration’s demise -- comprises a “meticulous record of the Watergate story from beginning to end,” university President Larry R. Faulkner said in a news conference.

As part of the extraordinary deal to purchase the materials, the university agreed to honor Woodward and Bernstein’s long-standing commitment to protect the identity of a number of confidential sources until their deaths, including “Deep Throat,” the Nixon administration official whose deep-background information was crucial to The Post’s pursuit of the Watergate story.

The collection, save for the papers that would reveal the identity of confidential sources, is to be catalogued, preserved and made available to scholars and the public within a year at the university’s Harry Ransom Humanities Research Center, one of the nation’s premier academic archives. The center’s holdings include a Gutenberg Bible, Shakespeare folios, the final proofs of James Joyce’s “Ulysses” and letters of Thomas Jefferson.

“Here was an institution that understood that some things would have to wait but that the great bulk of this material would be available,” said Woodward, 60, an assistant managing editor at The Post.

“People are now going to get a look at our work in a way that can be evaluated,” said Bernstein, 59. “Everybody else in this has been scrutinized. We haven’t. And we’re going to take a few hits in this.”

A moment later, Woodward stepped in to clarify Bernstein’s remark. The “hits” to which he referred might include the names and numbers of Bernstein’s former girlfriends scribbled among the papers, Woodward said.

The University of Texas at Austin is the nation’s largest and among the richest universities. Nonetheless, the price of the acquisition, to be financed by private gifts to the university, surprised some academic library and archives directors, who could not cite a comparable price paid to a living author for written materials.

“It’s unusual, there’s no doubt about that -- political collections do not normally bring this kind of money,” said Thomas Hickerson, associate university librarian at Cornell University and a recent president of the Society of American Archivists. “On the other hand, I won’t say that it’s outrageous. I think that for a political collection this is a biggie. This will really draw the attention of researchers. I think they have a unique body of material here.”

Hickerson said the University of Texas purchase is likely to have an inflationary effect, leading other contemporary authors, journalists and political figures to seek higher prices from research libraries for their papers. “This’ll be the new gold standard for these kinds of collections,” he said.

Victoria Steele, head of the department of special collections for the Young Research Library at UCLA, said she believed that UCLA had set a record for living authors last year by paying Susan Sontag, the author and critic, a reported $1.1 million for her papers, letters, manuscripts and a 20,000-book library.

On hearing of the $5 million price tag for the Watergate materials, Steele said: “Wow! . . . It is a lot of money. But I have to say it’s indisputably an important event.”

University of Texas officials acknowledged that the price, set by Woodward and Bernstein and not negotiated, was substantial and exceeded that paid for some other prominent acquisitions.

Walter Cronkite, the retired broadcaster and news anchor, donated his papers to the university, as did veteran broadcasters Harry Reasoner and Andy Rooney. The university also houses the old clippings morgue of the New York Times, which was donated, and one of five Gutenberg Bibles in the country, for which it paid $1.5 million in the 1980s.

Elsewhere, Francis Crick, a co-discoverer of DNA, sold his large collection of papers to the Wellcome Trust in 2001 for $1.3 million. And a page of Abraham Lincoln’s famous “house divided” speech was sold at auction for $1.5 million in 1992.

However, other historical documents and materials have fetched much higher prices, including the film of the Kennedy assassination shot by Abraham Zapruder, which he sold to the Smithsonian for $16 million in 1999, and the papers of Winston Churchill, purchased by the British government from the late prime minister’s family in 1995 for the sterling equivalent of $18.4 million.

Thomas F. Staley, director of the Ransom Center, said, “We were offered a fair price, and we felt this was the range.” The Watergate archive, he said, “only goes once -- it’s not like a rare book at auction.”

Staley said the materials acquired today, to be known as the Woodward-Bernstein Watergate Archive, “have a historic value in terms of presidential powers” and would be of interest to students and researchers in journalism, public policy, government, law and ethics.

He added: “In a sense I think we can begin to turn the tables on Woodward and Bernstein. When we open the archive next year, we will commence a long and fruitful interview with the pair.”

Woodward and Bernstein, a freelance writer, are to split the income. They also agreed to fund a $500,000 endowment at the university for the study of Watergate, journalistic ethics and the archive itself. In addition, the pair agreed to participate in a series of symposiums, lectures and other events.

University officials said they have raised more than half of the $5 million from institutional and individual sources, some with long-standing ties to the University of Texas. Additional fundraising is ongoing, said Faulkner.

“Bob Woodward and Carl Bernstein have taught more than one generation already, and through their lasting tie with the University of Texas at Austin, they will teach generations more,” Faulkner said.

The material in the archive will include more than 250 spiral notebooks, as well as typed office memos, audiocassette tapes and memorabilia. The two men have said they were fastidious about keeping virtually every scrap of documentation they accumulated in the course of their reporting, both for the newspaper and for their two books, “All the President’s Men” and “The Final Days.” That meant making and keeping notes on conversations not only with sources but also with editors at the paper, notably Benjamin C. Bradlee, The Post’s executive editor at the time, who oversaw the coverage of Watergate.

“It’s really interesting, even for us, to go back and look at all of this -- the particular agony of a number of people in the Nixon administration, why some of them helped us,” said Woodward. “It takes you back to that moment.”

Woodward said that only “a handful” of sources -- representing 1 to 2 percent of the archives -- would be protected from disclosure for the time being. In their cases, the materials are to remain in Woodward and Bernstein’s custody until the deaths of the sources, including Deep Throat. Then those documents, too, would be turned over to the Ransom Center.

In the event that Woodward and Bernstein die before “Deep Throat” or the other confidential sources, they said, a trustee named by them will have custody of the documents that reveal the sources’ identities. Eventually, all the materials will be turned over to the center.

Woodward declined to say whether he had asked Deep Throat for permission to reveal his identity.

“This is a part of history,” said Staley. “It’s not that we get the name of Deep Throat out there as soon as we get it.”