Jónsson, Eggert, Lars Lidgren, Bengt Mjöberg, Urban Rydholm, and Göran Selvik. 1990. “Humeral Cup Fixation in Rheumatoid Shoulders: Roentgen Stereophotogrammetry of 12 Cases”. Acta Orthopaedica 61 (2):116-17. https://doi.org/10.3109/17453679009006500.