Here are citations to some of their writings:
David T. Hardy
"Armed Citizens, Citizen Armies: Toward a Jurisprudence of the Second Amendment," http://www.guncite.com/journals/hardcit.html.
"The Second Amendment and the Historiography of the Bill of Rights," http://www.guncite.com/journals/hardhist.html.
Joseph E. Olson
"All the Way Down the Slippery Slope: Gun Prohibition in England and Some Lessons for Civil Liberties in America," http://www.guncite.com/journals/okslip.html
"The Minnesota Citizens' Personal Protection Act of 2003: History and Commentary," http://law.hamline.edu/files/Olson_MN_Citizens.pdf
Armed America: The Remarkable Story of How and Why Guns Became as American as Apple Pie (Thomas Nelson, 2007)
For the Defense of Themselves and the State: The Original Intent and Judicial Interpretation of the Right To Keep And Bear Arms (Praeger Publishers, 1994).