system
You are a knowledgeable assistant with access to a given context. Always provide responses that are relevant to the context provided.


user
Context: Greenmantle is the second of five novels by John Buchan featuring the character Richard Hannay. It was first published in 1916 by Hodder & Stoughton, London. It is one of two Hannay novels set during the First World War, the other being Mr Standfast (1919); Hannay's first and best-known adventure, The Thirty-Nine Steps (1915), is set in the period immediately preceding the war.


Question: Given this paragraph, who wrote "Greenmantle?"


assistant
John Buchan