@book{Fossen2012,
author = {Fossen, Frank M. and Büttner, Tobias J. M.},
year = {2012},
language = {eng},
copyright = {http://www.fu-berlin.de/sites/refubium/rechtliches/Nutzungsbedingungen},
title = {The returns to education for opportunity entrepreneurs, necessity entrepreneurs, and paid employees},
url = "http://dx.doi.org/10.17169/FUDOCS_document_000000014403",
}