More than a dozen professors at schools including Princeton and Harvard universities have come to the defense of Edin and Kefalas, calling the charge of conceptual plagiarism "absurd."
In response, Anderson compiled a list of 22 similarities between the books - both examine motherhood and marriage in the inner city - and posted the comparison on the Penn Almanac, a university Web site.
Last Tuesday, a letter signed by 110 scholars who support Anderson appeared on the Almanac.
The next steps are uncertain. Neither side has filed an official complaint at Penn, which would trigger a more formal inquiry by the university.
The dispute could have ended last summer, when Anderson and Edin met to discuss their books, eventually reaching a confidential agreement.
But in August, the issue became the talk of the American Sociological Association conference, held in Philadelphia. Afterward, disturbed by what he saw as official silence, Penn professor emeritus Harold Bershady sent an e-mail to the department faculty, making the charge of "conceptual plagiarism."
When his e-mail was leaked to The Daily Pennsylvanian - the student newspaper that first reported the controversy - the furor ignited publicly.
Just goes to show how important it would be to detail attempts at cheating on a university level.