Zetterberg, Carl, Roland Björk, Roland Örtengren, and Gunnar B. J. Andersson. 1984. “Electromyography of the Paravertebral Muscles in Idiopathic Scoliosis: Measurements of Amplitude and Spectral Changes under Load”. Acta Orthopaedica 55 (3):304-9. https://doi.org/10.3109/17453678408992362.