The evidence from lamps is summarized by Eric C. Lapp in Sepphoris in Galilee, pp. 221–222, and “The Archaeology of Light: The Cultural Significance of the Oil Lamp from Roman Palestine” (Ph.D. diss., Duke Univ., 1997), esp. pp. 80–113. The relevant numismatic data is conveniently summarized by Ya’akov Meshorer in Sepphoris in Galilee, pp. 195–198.