In 2002 Judy Tzu-Chun Wu came across a newly published anthology on the American West. Ms. Wu, then an assistant professor of history at Ohio State University's main campus, often wrote and taught about the American West, so she began flipping through the book. She was surprised when she saw a chapter on Margaret Chung, the first U.S.-born female Chinese doctor, who also happened to be the subject of Ms. Wu's 1998 dissertation.

"I remember thinking it was odd that someone else was working on Margaret Chung," says Ms. Wu. "I thought, How does this person's take compare to mine?"

This person -- Benson Tong, then an assistant professor of history at Wichita State University -- had a similar take. Very similar. In fact, as she read, Ms. Wu's curiosity turned into anger: The chapter was nothing more than a condensed version of her dissertation, she believed. There were phrases and descriptions that seem to have been lifted nearly verbatim, along with unattributed facts Ms. Wu had spent long hours pinning down.

It was not that Mr. Tong had simply claimed large blocks of Ms. Wu's dissertation as his own. He cited Ms. Wu's dissertation multiple times. Those citations, however, don't tell the whole story.

Ms. Wu went through Mr. Tong's chapter word by word. She highlighted in yellow those portions of the text that were borrowed directly or altered slightly. She highlighted in green those sections that were paraphrased versions of her arguments and research. When she was finished, only one paragraph of the 15-page essay had escaped the highlighter.

But the most damning evidence could be found in the footnotes. If Mr. Tong's list of sources was to be believed, he had gone to the same archives, reviewed the same unpublished manuscripts, oral histories, and newspaper articles as Ms. Wu and then chosen to quote identical passages from that material. "Almost all of the citations in Tong's essay exactly replicate the sources and page numbers that appear in my footnotes," Ms. Wu wrote in a complaint to the American Historical Association.

She submitted a 21-page complaint to the association and wrote a letter to Scholarly Resources Inc., the publisher of Mr. Tong's book. Mr. Tong offered a rebuttal to Ms. Wu's charges, and Ms. Wu countered with a response of her own, again laying out the evidence against him.

As was the association's custom, it sent a letter to Ms. Wu and Mr. Tong informing them of its decision about Ms. Wu's complaint.

As a result, Ms. Wu felt it was her responsibility to publicize the findings. She had the chairman of her department fax the association's letter to the chairman of the history department at Wichita State.

That was particularly bad timing for Mr. Tong, who was coming up for tenure. He was turned down. After sticking around Wichita State for another year, he was hired by Gallaudet University.

When contacted recently at the university, Mr. Tong asks the caller to hold on while he closes his office door. He contends that he "didn't make any mistakes" in the essay and says he refuted Ms. Wu's allegations. When asked if he was guilty of plagiarism, he responds, "No, I don't think so at all."

However, he declined to discuss any details, saying the matter had already been put to rest. When asked whether his new employer was aware of the historical association's finding, he said: "I guess they know about it. The word does get around."

Apparently word had not gotten around to the chairman of the government and history department at Gallaudet, Russell Olson. Upon being told that a newly hired member of his department had been found guilty of plagiarism, Mr. Olson groans. When asked if this came as a surprise, Mr. Olson answers, "Total." He went on to say he would "do something" but declined to be more specific.

As for Ms. Wu, she feels somewhat vindicated by the historical association's ruling. Still, she remains frustrated that Mr. Tong's book has never been retracted. "It's still out there," she says.

Her dissertation is scheduled to be published next year by the University of California Press. Ms. Wu worries that Mr. Tong might even be asked to review her book. After all, he's written on the same subject.