Thief: The Dark Project Easter Egg - If I Had a Hammer...

In the chapter "Strange Bedfellows", you can find a book in the library which says:

"Hadst I a hammer, wouldst I hammer in the morning. Wouldst I hammer in the evening, all over this land."

This is a reference to the quite famous song "If I Had a Hammer". The song begins like this:

If I had a hammer / I'd hammer in the morning / I'd hammer in the evening / All over this land