Potential recession triggers
Trade wars with China and other countries, along with restrictions on migration, foreign direct investment, and technology transfers, could have profound implications for global supply chains, raising the threat of stagflation (slowing growth alongside rising inflation). And the risk of a US growth slowdown has become more acute now that the stimulus from the 2017 tax legislation has run its course.
The Growing Risk of a 2020 Recession and Crisis
By: Nouriel Roubini – New York University
10 year yields have declined in advanced countries

Down, Down, Down: 10 Year Yields in Advanced Countries
By: Menzie Chinn – University of Wisconsin–Madison
Which spread is the best predictor of recessions
David Miller argues that testing models derived from the yield curve shows that a principal components decomposition of the yield curve is the most robust predictor of recessions.

There is No Single Best Predictor of Recessions
By: David S. Miller – Federal Reserve Board