Hox J. J. Multilevel analysis : techniques and applications 2nd ed. : New York : Routledge : 2010 : p. cm. : ISBN: 978-1-84872-845-5 (hardback : alk. paper) Mandatory Search the University Library catalogue
Pallant Julie SPSS survival manual : a step by step guide to data analysis using SPSS for Windows senaste upplagan : Maidenhead : Open University Press : ISBN: 0-335-22366-4 (spiralh.) Mandatory Search the University Library catalogue
Creswell John W. Qualitative inquiry & research design : choosing among five approaches 2. ed. : Thousand Oaks : SAGE : cop. 2007 : xvii, 395 s. : ISBN: 1--41291607-0 (hft.) Mandatory Search the University Library catalogue