Pressure measurement of 10-10 to 10-12 Pa by nonresonant multiphoton ionization Kokubun, K. ; Sekine, S. ; Ichimura, S. ; Kurokawa, A. ; Shimizu, H. Abstract Publication: Vacuum Pub Date: June 1996 DOI: 10.1016/0042-207X(96)00019-X Bibcode: 1996Vacuu..47..557K