Media type: E-Article Title: Are Older Workers Harmful for Firm Productivity? Contributor: Lallemand, Thierry; Rycx, François imprint: Springer Science and Business Media LLC, 2009 Published in: De Economist Language: English DOI: 10.1007/s10645-009-9126-5 ISSN: 0013-063X; 1572-9982 Origination: Footnote: