The Hamilton wrist: a four-revolute-joint spherical wrist without singularities. - Gregory L. Long; Richard P. Paul; William D. Fisher (ICRA, 1989)

A pantograph linkage parallel platform master hand controller for force-reflection. - Gregory L. Long; Curtis L. Collins (ICRA, 1992)

Regional Structure Kinematic Modules for Singularity Avoidance. - Gregory L. Long; Scott W. Reed; Joseph P. Donoghue (ICRA (1), 1993)

On the Duality of Twist/Wrench Distributions in Serial and Parallel Chain Robot Manipulators. - Curtis L. Collins; Gregory L. Long (ICRA, 1995)

The singularity analysis of an in-parallel hand controller for force-reflected teleoperation. - Curtis L. Collins; Gregory L. Long (IEEE Trans. Robotics Autom., 1995)