This footnote isn’t quite right. There are a lot of people who have done work to specify the term “commons” especially as it has applied to the digital domain. Boyle’s work has done more than anyone to popularize the concept, but it builds on many others. The most important work not mentioned here is that of Yochai Benkler, who was into commons-talk way before it was cool. His work re-introduced questions about the public domain, about “enclosures movements” and
See especially:
Free as the Air to Common Use: First Amendment Constraints on Enclosure of the Public Domain, 74 N.Y.U. Law Review 354 (1999)
Overcoming Agoraphobia: Building the Commons of the Digitally Networked Environment, 11 Harvard Journal of Law & Technology 287 (1998) 
The Commons As A Neglected Factor of Information Policy (working draft presented at Telecommunications Policy Research Conference 9/98)

There is a long list of others in legal scholarship who have thought about this issue as well. One good list is for the “Free Information Ecology in the Digital Environment” conference from 2000

One might also note in this context that the revival of thinking about commons rarely references the economic anthropology tradition of the study of common-property and common-tenure, which works are legion. Ostrom and Ellickson refer in some places to the tradition of ethnographic analysis of exchange, but it is for the most part absent. There many places to start an investigation of this history, a recent one is David Graeber’s Towards an Anthropological Theory of Value”