Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI) Ady Hershcovitch,Selective deposition of radio-frequency power in volume sources to optimize the tandem configuration for negative ion production,Review of Scientific Instruments,0034-6748,AIP Publishing,1994-04-01,65,4,1170-1172,https://cir.nii.ac.jp/crid/1360574096327703296,https://doi.org/10.1063/1.1145047