From Tolkien Gateway
- "The Authorities, it is true, differ whether this last question was a mere ‘question’ and not a ‘riddle’ according to the strict rules of the Game."
- ― Prologue
- J.R.R. Tolkien, The Lord of the Rings, "Prologue", "Of the Finding of the Ring"
- Michael Martinez, "Are There Any Christian Themes in The Hobbit?", Middle-earth and J.R.R. Tolkien News & Articles (accessed 1 October 2022); note that the reference is wrong, as the Authorities aren't mentioned in Riddles in the Dark.
- Robert Foster, The Complete Guide to Middle-earth, entry "Authorities", according to information from Dick Plotz.
- J.R.R. Tolkien, Christopher Tolkien (ed.), The War of the Jewels, "Part Four. Quendi and Eldar: Appendix D. *Kwen, Quenya, and the Elvish (especially Ñoldorin) words for 'Language': Note on the 'Language of the Valar'"