Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI) Q. Tang and S. Ogura and M. Yamasaki and K. Kikuchi,Experimental study on intermediate and gradient index dielectric thin films by a novel reactive sputtering method,"Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films",0734-2101,American Vacuum Society,1997-09-01,15,5,2670-2672,https://cir.nii.ac.jp/crid/1363951794133610112,https://doi.org/10.1116/1.580940