As The New York Times reports, the long-rumored secret archive of iconic folksinger Bob Dylan has been revealed as very real, and now the extensive collection is being acquired by a group of institutions based in Oklahoma. The reported price tag on the archive is $15 million–$20 million, with an appraised value of up to $60 million. The buyers are headed up by the George Kaiser Family Foundation and the University of Tulsa, and the deal was brokered by New York rare-book dealer Glenn Horowitz.

The archive is a treasure trove of Dylan history and lore, containing 6,000 pieces of correspondence, multimedia and countless manuscripts and drafts of lyrics from Dylan’s entire career, early days to latter days, providing a potential window into the process of one of the most enigmatic and prolific musicians and writers in American history. As the Times writes:

Classics from the 1960s appear in coffee-stained fragments, their author still working out lines that generations of fans would come to know by heart. (“You know something’s happening here but you,” reads a scribbled early copy of “Ballad of a Thin Man,” omitting “don’t know what it is” and the song’s famous punch line: “Do you, Mister Jones?”) The range of hotel stationery suggests an obsessive self-editor in constant motion.

Dylan himself seems pleased with the purchase, saying that he is glad that the archives “are to be included with the works of Woody Guthrie and especially alongside all the valuable artifacts from the Native American nations. To me it makes a lot of sense, and it’s a great honor.” The Woody Guthrie archive was acquired by the foundation five years ago and built a mini-museum to display it in downtown Tulsa, an honor that will likely be afforded to Dylan’s collection as well.

Princeton historian Sean Wilentz, who penned Bob Dylan in America, had this to say about the archive’s significance: “It’s going to start anew the way people study Dylan.”