1. Andersson GBJ, Örtengren R, Nachemson A (1977) Intradiskal pressure, intra-abdominal pressure and myoelectric back muscle activity related to posture and loading. Clin Orthop Rel Res 129:156–164
2. Bakke S (1931) X-ray study on spinal motion [in German, Röntgenologische Beobachtung über die Bewegungen der Wirbelsäule]. Acta Radiol, Suppl. 13
3. Basmajian JV, De Luca CJ (1985) Muscles alive—their functions revealed by electromyography. William & Wilkins, Baltimore
4. Benninghoff A, Goerttler K (1980) Textbook of human anatomy, vol 1: general anatomy, cytology and musculoskeletal system (13th edn) [in German: Lehrbuch der Anatomie des Menschen, Bd 1: Allgemeine Anatomie, Cytologie und Bewegungsapparat 13. Aufl] Urban & Schwarzenberg, München, Germany
5. Bradford FK, Spurling RG (1945) The intervertebral disc. Charles C Thomas, Springfield