George O'Brien authored numerous works in the field of economics including An Essay on Medieval Economic Teaching, Labour Organisation, and Agricultural Economics. His work on the economic history of Ireland, published in 1921, has not been superceded to date. He occupied the post of professor of national economy at University College, Dublin, for 35 years, and also participated in debates on economic matters in the Irish Senate. Edward A. McPhail is an assistant professor of economics at Dickinson College in Carlisle, Pennsylvania.