Williams, D. (2011). Multiple Language Usage and Earnings in Western Europe (1–). International Journal of Manpower. https://doi.org/http://dx.doi.org/10.1108/01437721111148513
Williams, Donald. 2011. “Multiple Language Usage and Earnings in Western Europe”. International Journal of Manpower. https://doi.org/http://dx.doi.org/10.1108/01437721111148513.
Williams, Donald. Multiple Language Usage and Earnings in Western Europe. International Journal of Manpower, 1 July 2011, https://doi.org/http://dx.doi.org/10.1108/01437721111148513.