Monetary Policy and Real Borrowing Costs at the Zero Lower Bound

Simon Gilchrist, David López-Salido, and Egon Zakrajšek, Lessons from the Financial Crisis for Monetary Policy (American Economic Journal: Macroeconomics, Volume 7, no. 1, 2013), chap. 3, https://www.nber.org/books-and-chapters/lessons-financial-crisis-monetary-policy/monetary-policy-and-real-borrowing-costs-zero-lower-bound.