Gabriel (Supernatural), Villains Wiki
Gabriel - Super-wiki
Supernatural send-off: Richard Speight Jr. on season 2's Tall Tales
Interview: Rob Benedict and Richard Speight, Jr. Discuss 'Supernatural Then and Now' Rewatch Podcast [EXCLUSIVE] - Nerds and Beyond
Richard Speight, Jr. calls conventions Broadway version of 'Supernatural' - Nerd Alert News
Richard Speight Jr., Supernatural Wiki
From Trickster to Director: An SPN Family Journey With Richard Speight Jr. – Fangasm
James Randi - Wikipedia
5 Facts about Supernatural's Richard Speight Jr. you probably didn't know – SheKnows
Saving People, Hunting Things, The Family Business. – Miss Raee