Lithell , H., B. Vessby, K. Hellsing, K. Ljunghall, N.-J. Höglund, I. Werner, and Å. Bruce. 1983. “Changes in Metabolism During a Fasting Period and a Subsequent Vegetarian Diet With Particular Reference to Glucose Metabolism”. Upsala Journal of Medical Sciences 88 (2):109-19. https://doi.org/10.3109/03009738309178444.