Unemployment and Underemployment in Historical Perspective Session B-9 ; Growth and Stagnation in the Mediterranean World in the 19th and 20th Centuries : Session B-10 ; Models of Regional Economies in Antiquity and the Middle Ages to the 11th Century : Session B-11 ; Methodological Problems : Session B-12 a ; Historical Information Systems : Session B-12 B : Proceedings by Erik Aerts | Menrva Books | MenrvaBooks