Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI) Kyoji Yamashita and Tomohide Watanabe and Ikunao Isomura and Hideo Tsuchiya,Gray map reference pattern generator of a die-to-database mask inspection system for 256-Mb and 1-Gb DRAMs,SPIE Proceedings,0277-786X,SPIE,1998-09-01,3412,,544,https://cir.nii.ac.jp/crid/1872272492575996928,https://doi.org/10.1117/12.328834