The Star Tribune recently sought input from Doug Green, professor of English at Augsburg College, on the disputed authorship of the stage drama “Pericles, Prince of Tyre,” which is being performed at the Guthrie Theater in Minneapolis.

Many believe that the first two acts of the play were written by an unknown playwright, but that the final three acts were written by William Shakespeare. Others believe that Shakespeare started the work early in his career and finished it after he had gained more experience. One piece of evidence in support of dual authorship is the play’s absence from the “first folio,” the first collection of plays Shakespeare published.

“If it’s not in the First Folio, people are skeptical,” said Green. “Almost from the get-go, the first two acts don’t look like Shakespeare. We know it was played by the King’s Men and it sounds like Shakespeare but it is pretty clear that Shakespeare had a major hand in the last three acts.”

Read: Act One for Joe Haj: ‘Pericles’ gives Guthrie audiences a look at his work on the Star Tribune site.