Complete description of the study that the photographs are part of is available in the following scientific publication: Olsson, O. & Hentati-Sundberg, J. 2017. Trends and status of four seabird species at Stora Karlsö i...
Forskningsgruppen för samhälls- och informationsstudier
In this survey the contents of 21 Swedish weeklies are scrutinized for the period 1920-1975. Four issues of each paper have been examined for each five years.