Philp, B., and D. Wheatley. “European Work Time Regulation, Surplus-Value and Underemployment Among Full-Time Employees: A Cross-Sectional Analysis Using the 2009 EU LFS”. Economic Issues, vol. 18, no. 1, Mar. 2013, pp. 57-74, https://mail.economicissues.org.uk/index.php/EI_OJS/article/view/201.