Gingerich, O., & Westman, R. S. (1988). The Wittich connection: Conflict and priority in late sixteenth-century cosmology. Philadelphia: American Philosophical Society.

Gingerich, Owen., and Robert S. Westman. The Wittich Connection: Conflict and Priority in Late Sixteenth-century Cosmology. Philadelphia: American Philosophical Society, 1988.

Gingerich, Owen., and Robert S. Westman. The Wittich Connection: Conflict and Priority in Late Sixteenth-century Cosmology. Philadelphia: American Philosophical Society, 1988.