Board Thread:General Mod Discussion/@comment-25981649-20170624004847/@comment-30248910-20170630164840

High King Ithilion wrote: It's in The Peoples of Middle-earth, Of Dwarves and Men.

Ithilion, Discussions Moderator (Auta i lómë) 15:42, June 30, 2017 (UTC) Yeah, there's the following footnote referencing the Dwarves exchanging metal and smiths with Men for scouts:

"29 No Dwarf would ever mount a horse willingly, nor did any ever harbour animals, not even dogs."

If you have the three-volume ​History of Middle-earth​ publish by Harper Collins, you can find it on page 323 of the third volume

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