sentences:  He was Visiting professor at the Lisbon University Institute (ISCTE), in Portugal from 2007 to 2013.Among his other professional engagements, he has been Jean Monnet Visiting Professor at the European University Institute, Florence, Italy, 2002; Visiting Scholar, Stanford University, Spring, 2002, Spring, 2004–2008; Fellow at Swedish Collegium for Advanced Study in the Social Sciences (Spring, 1992; Autumn, 1998), and Fellow at the European University Institute (Spring, 1998).Beginning in the early 1970s, Burns collaborated with a number of researchers, such as Thomas Baumgartner, Walter F. Buckley, Matthew Cooper, Philippe DeVille, David Meeker, Bernard Gauci, among others.