By Nordisk Familjebok AB (Ltd) – Swedish Encyklopedia "Nordisk Familjebok", third edition, 1923 – 1937 in 17 volymes + 1937-1939 3 supplementary volymes. This is from volyme 7, article is "Fotboll" (Football). This volyme frist published 1928.or 1929., Public Domain, https://commons.wikimedia.org/w/index.php?curid=41088871