HelbrechtI., Izsák Éva, DirksmeierP., BerkiM., and SchlueterS. “The Changing Nature of Labour Protest: Comparing the Fragmentation of Protest Rituals on May 1st in Berlin and Budapest”. Hungarian Geographical Bulletin, Vol. 66, no. 2, July 2017, pp. 95-111, doi:10.15201/hungeobull.66.2.1.