Hartvig , P. ., Gustafsson , L. L. ., Bergström , K. ., Moström , U. ., Pontén , U. ., Lindberg , B. ., & Lundqvist , H. . (1987). Positron Emission Tomography: An Animal Model of Spinal Distribution of Drugs after Intrathecal Administration. Upsala Journal of Medical Sciences, 92(2), 205–213. https://doi.org/10.3109/03009738709178690