 Complete the following phrase:  Ludwig Guttmann at the Stoke Mandeville Hospital began experimenting with spinal cord injury sport classification systems during the 1940s using a medical based system. His classification system was formally formalized in 1952 at the Stoke Mandeville Hospital. This system was published in the Handbook of Rules, which was distributed to people involved with paraplegic sport at the time including coaches, doctors and physiotherapists in various countries. At the time, this classification system was a medical classification. The classification system has historically been based around the one used for athletics. Guttmann was subsequently adopted by the International Stoke Mandeville Wheelchair Sports Federation ISMWSF at their founding in 1960, when the first 