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)