How Trends and Fluctuations Are Observed, Modeled, and Simulated: An Introduction

Victor Zarnowitz, Business Cycles: Theory, History, Indicators, and Forecasting (University of Chicago Press, 1992), chap. 6, https://www.nber.org/books-and-chapters/business-cycles-theory-history-indicators-and-forecasting/how-trends-and-fluctuations-are-observed-modeled-and-simulated-introduction.