title: Monitoring linear accelerator output constancy using the PTW Linacheck.
authors.affiliation: Radiotherapy Physics Section, Department of Medical Physics and Clinical Engineering, Churchill Hospital, Oxford Radcliffe NHS Hospitals Trust, Headington, Oxford, UK. garry.mcdermott@orh.nhs.uk
authors.forename: Garry M
authors.initials: GM
authors.lastname: McDermott
authors.forename: Andrew H
authors.initials: AH
authors.lastname: Buckle