@article{doi:10.1302/0301-620X.47B3.425, author = {Marquardt, Ernst}, title = {THE HEIDELBERG PNEUMATIC ARM PROSTHESIS}, journal = {The Journal of Bone & Joint Surgery British Volume}, volume = {47-B}, number = {3}, pages = {425-434}, year = {1965}, doi = {10.1302/0301-620X.47B3.425}, url = {https://doi.org/10.1302/0301-620X.47B3.425} }