Handwritten notes by Queen frontman Freddie Mercury suggest that the legendary singer toyed with calling the band’s classic hit “Mongolian Rhapsody” rather than “Bohemian Rhapsody.”

The revelation comes as many of Mercury’s former possessions are set to go up for auction. Mary Austin, Freddie’s longtime friend and companion, has decided to sell several of the items she inherited from the Queen singer. Among them are early lyrics to “Bohemian Rhapsody.”

The notes were hand-scribbled onto a notepad for British Midland Airways, an airline that began in 1964 and lasted until its acquisition by British Airways in 2012. Mercury appears to have been testing out various lyrics for his song idea. One page features an assortment of phrases, including “fandango,” “Figaro,” “thunderbolts and lighting” and “belladonna.”

Still, it’s the word “Mongolian” crossed out and replaced by “Bohemian” that has grabbed people’s attention. The New York Times spoke to several Queen historians who had never before heard of the alternative title. They also weren’t surprised.

Watch Queen’s ‘Bohemian Rhapsody’ Video

Mark Blake, author of Is This the Real Life?: The Untold Story of Queen, noted the band often “had joke titles for things.” Jim Jenkins, one of Queen’s official biographers, admitted he’d never heard of “Mongolian Rhapsody” but added that Mercury “never liked to explain” his lyrics or titles.

Released in 1975, “Bohemian Rhapsody” would become one of Queen’s defining songs, a sprawling operatic track that remains one of the most famous in rock history. Unsurprisingly, Mercury’s early drafts of the song are expected to fetch a high price when they come to auction in September. The notes are estimated to be worth $1.5 million.