The singer made a sketch of the lyrics of the song with the name Mongolian Rhapsody on the letterhead of the British Midland airline, on which you can see the calendar for 1974, while the track was recorded in August 1975. Mercury first wrote "Mongolian Rhapsody", and then crossed out the first word and added "Bohemian" on top.
On another page of working drafts, an alternative to the well-known second verse is presented.
Dr. Gabriel Heaton, Sotheby's Books & Manuscripts specialist, noted:
Early drafts like these are easily lost or discarded, so the rare surviving manuscripts give us a fascinating insight into how his songs were developed and composed, as well as remind us of their musical complexity and sophistication.
The revelations on these pages include the extensive reworking that was part of the songwriting process, and his amazing attention to the plans for vocal harmonies that have become a hallmark of Queen's sound.