“…To construct Trade-Expansion, we have, first, recorded on-site occurrences of the selected materials and their positions within the local stratigraphy (Massa and Palmisano, 2018b: 66). This information is available from Massa and Palmisano (2018a), Quenet (2008) and the polity-specific secondary sources listed in the Internet Appendix. Next, we have harmonized local archaeological phasing through regional chrono-stratigraphic synchronizations (e.g., Lebeau, 2011Lebeau, , 2018Rova, 2019;Finkbeiner et al, 2015) and we have assigned absolute dates to the sampled assemblages.…”