Håkansson Gisela Tvåspråkighet hos barn i Sverige. Lund : Studentlitteratur : 2003 : 217, [7]s. : ISBN: 91-44-03070-3 Search the University Library catalogue
How languages are learned. Lightbown Patsy M., Spada Nina 2., rev. ed. : Oxford : Oxford Univ. Press : cop. 1999 : xvi, 192 s. : ill., tab. : ISBN: 0-19-437000-3 Search the University Library catalogue