Undervisningsdirektoratet (2013). The Norwegian Directorate for Education and Training; Natural Science Subject Curriculum.

Undervisningsdirektoratet (2013). The Norwegian Directorate for Education and Training; Natural Science Subject Curriculum. Retrieved on the 30th of April 2018 from: http://www.udir.no/kl06/NAT1-02/Hele/Formaal?lplang=eng