I first studied this some 50 years ago, so it's a little tough to remember all the information. But here is an excerpt that might give you some sources to chase:
Verses 16-17: Selling and buying was limited only to those who bore the mark, i.e. “the name of the beast or the number of its name.” David Clark comments, “This was to boycott or ostracize the Christians, and deprive them of the common rights of citizens, or the common rights of humanity. The pressure of economic distress was to be laid on them to compel them to conform” (Steve Gregg, p. 304). David Chilton adds, “Similarly [the Jewish leaders] organized economic boycotts against those who refused to submit to Caesar as Lord, the leaders of the synagogues ‘forbidding all dealings with the excommunicated,’ and going as far as to put them to death.” [Here Chilton partially quotes from Austin Farrer in his 1964 work entitled The Revelation of St. John the Divine (p. 157).] Richard Anthony (2009) speaks further of the allegiance required by Nero during his lifetime:
All those under the jurisdiction of Rome were required by law to publicly proclaim their allegiance to Caesar by burning a pinch of incense and declaring, “Caesar is Lord”. Upon compliance with this law, the people were given a papyrus document called a “libellus”, which they were required to present when either stopped by the Roman police or attempting to engage in commerce in the Roman marketplace, increasing the difficulty of “buying or selling” without this mark (emphasis added).
In the first post for chapter 13 we also saw a quote from C. Marvin Pate and Calvin B. Haines Jr., from their 1995 book entitled Doomsday Delusions, in which they said,
Megalomaniac that he was, Nero had coins minted in which he was called “almighty God” and “Savior.” Nero’s portrait also appears on coins as the god Apollo playing a lyre. While earlier emperors were proclaimed deities upon their deaths, Nero abandons all reserve and demanded divine honors while still alive (as did also Caligula before him, AD 37-41). Those who worshipped the emperor received a certificate or mark of approval – charagma, the same word used in Revelation 13:16 [the famed mark of the beast].