The original manuscript of one of the most iconic rock songs of all times is set to hit the auction block, Reuters reports. The 16 page hand-written and typed draft of Don McLean’s American Pie could fetch up to $1.5 million when it goes on auction at Christie’s on April 7.

While the eponymous record, released in 1971, mirrors the major social changes in the US in the 1960s and 1970s, the title song famously refers to the deaths of rock and roll legends Buddy Holly, Ritchie Valens, and J. P. Richardson in a plane crash in 1959 as “The Day the Music Died.”

McLean has always been very secretive about the meaning of the rest of the lyrics. He told Reuters, “I wanted to capture, probably before it was ever formulated, a rock-and-roll American dream.” He added, “The writing and the lyrics will divulge everything there is to divulge.”

The song has been voted Song of the Century by the Recording Industry Association of America and the National Endowment of the Arts.

Francis Wahlgren, head of Christie’s Printed Books and Manuscripts department said, “The fact that the drafts, the working process of it, are all being offered at this lot makes it a remarkable insight into the mind of Don McLean.”

Wahlgren predicted that the manuscript will be popular with bidders, “We’ve seen records double or triple for manuscripts in a matter of years because there has been a heightened interest in those very rare and truly significant manuscripts that come on the market.”

The current record price for song lyrics at auction stands at $2 million, set last year by Bob Dylan’s draft for Like a Rolling Stone.