1
Published 2007
Ministry of Labor and Social Affairs, Spain

2
Published 2009
Dirección General de Tráfico

3
Published 2008
Ministry of Labor and Social Affairs, Spain

4
Published 2009
Dirección General de Tráfico

5
Published 2009
Santillana, Mexico

6
Published 2010
Universidad Catolica Cardenal Raul Silva Henriquez

7
Published 2004
OECD Publishing

8
Published 2007
Ministry of Labor and Social Affairs, Spain

9
Published 2005
OECD Publishing

10
Published 2007
Ministry of Labor and Social Affairs, Spain

11
Published 2010
Ministry of Health, Spain

12
Published 2010
Instituto Nacional de Administración Pública

13
Published 2005
Fundacion E

14
Published 2009
Ministry of Labor and Social Affairs, Spain

17
Published 2017
OECD Publishing

18
Published 2017
OECD Publishing

19
Published 2012
Corporación de Investigación, Estudio y Desarrollo de la Seguridad Social 

20
Published 2015
OECD Publishing