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Books about Thrain:
Avelon Chapter 3 Part 2 of 5 the Legacy of Thrain (1999)
En flanant travers la France. Autour de Paris. Deuxime srie. Versailles, Saint-Cloud, le chteau du Val, Meulan... by Andre. Hallays (1921)
Wiki information Thrain:
Thráin II is a fictional character in J. R. R. Tolkien's legendarium. He is first mentioned in The Hobbit, and more of his history is given in Unfinished Tales.