Chung, C., Ka, H., Wang, H., Ding, D., Kelleher, A., & Cooper, R. (1969). Performance Evaluation of a Mobile Touchscreen Interface for Assistive Robotic Manipulators: A Pilot Study. Topics in Spinal Cord Injury Rehabilitation, 23(2), 131-139. https://doi.org/10.1310/sci2302-131 (Original work published 1969)