@unpublished{Adda2009,
author = {Jerome Adda and Christian Dustmann and Costas Meghir and Jean-Marc Robin},
title = {Career progression and formal versus on-the-job training},
year = {2009},
month = {Jan},
doi = {10.1920/wp.ifs.2009.0906},
issn = {1742-0415},
url = {http://www.ifs.org.uk/wps/wp0906.pdf},
}