When librarians in a township in northern France began wondering late in 2014 whether their centuries-old book of Shakespeare’s works might be a rare copy of the First Folio, they put in a call one of the world’s greatest authorities on the subject. Eric Rasmussen traveled to St. Omer, examined the beat-up book, and made the verification.

Few, if any, know the Folio like Rasmussen, a professor and chair of the English Department at the University of Nevada at Reno and co-editor of The Shakespeare First Folio: A Descriptive Catalogue. Marking the opening of the exhibit First Folio! The Book that Gave Us Shakespeare at the Library, he discusses the Folio and his work, including two decades of research that went into identifying 232 surviving copies of the treasured volume (the one in France was the 233rd).