Recreating exactly what happened, and why, is difficult, because most of the parties are reluctant to talk about it — and in fact agreed not to as part of the mediated settlement reached over the summer. But it went something like this:

Last March, the University of California Press published Promises I Can Keep: Why Poor Women Put Motherhood Before Marriage, by Kathryn Edin, an assistant professor of sociology at Penn, and Maria Kefales, an assistant professor at Saint Joseph’s University.

Some time soon after that, Elijah Anderson, a senior sociologist and fellow researcher on poverty at Penn, approached her with what the chairman of the sociology department, Paul D. Allison, describes as a “disagreement” about her book, reportedly citing concerns that its ideas bore a strong resemblance to those in two of Anderson’s previous works.

“Over the summer,” Allison said in a prepared statement, “they repeatedly discussed the issues that separated them and they eventually resolved their differences privately. Although not a direct participant in their discussions, I was in frequent contact with Edin and Anderson during that time, and I know that they worked very hard to reach an amicable resolution of the issues. At the time, all parties expressed full satisfaction with their agreement.”

In an interview Wednesday, the dean of Penn’s School of Arts and Sciences, Rebecca Bushnell, said that the department had followed the procedures laid out publicly in Penn’s faculty handbook for resolving disputes that, as she put it, “fall into the broad category of [alleged] misconduct in research.”

Bushnell and Allison both emphasized that no formal complaints were filed, which would have resulted in a more formal process involving the Faculty Senate. The deliberations were mediated, Bushnell said, although “I can’t discuss who was there,” but “it was very conscientiously and thoroughly handled, and, as far as I was concerned, settled.”

But apparently not as far as Harold Bershady was concerned. Bershady, an emeritus professor who retired in 2002, sent an e-mail last week on an internal listserv for the sociology department, in which, according to The Daily Pennsylvanian — which first reported on the situation — he accused Edin of taking ideas and concepts from Anderson’s work “practically wholesale.”