collider.com -BY MICHAEL JOHN PETTY -Before 'The Winchesters' premieres this fall, we've brushed up on the 'Supernatural' lore to reveal all we know about the Men of Letters.
screenrant.com -BY SAIM CHEEDA -From John and Mary’s love story to the Men of Letters’ background, The Winchesters has changed quite a bit of Supernatural’s established history.