Format by Jim R. Buchanan, 6/11/96 GDS II Graphic Design System User's Operating Manual, First Edition 1978 // Calma Interactive Graphic Systems, November 1978. Retrieved Apr 21, 2020. GDSII™ Stream Format Manual (B97E060), Release 6.0 // Calma, February 1987 SPIE Handbook of Microlithography, Micromachining and Microfabrication, Vol. 1: Microlithography // Bellingham, Wash. : SPIE Optical Engineering Pr., 1997, 2.9 Appendix: GDSII Stream Format Details of GDSII format including illustrations EDA file formats