Covariant Specification. - David L. Shang (ACM SIGPLAN Notices, 1994)

Covariant Deep Subtyping Reconsidered. - David L. Shang (ACM SIGPLAN Notices, 1995)

A Method for Using Object-Oriented Frameworks to Support Various High-Level Parallel Computing Models. - Lu Pei; Dachuan Yu; Lu Jian; David L. Shang (TOOLS (24), 1997)