I want to know the answer to the following question:
What was the name of the book Wittgenstein published in 1921?
All the background I'm provided with is that "As a result of their family relationship, Hayek became one of the first to read Wittgenstein's Tractatus Logico-Philosophicus when the book was published in its original German edition in 1921.". Is that enough to answer the question?