GOV.UK, National Crime Agency, Forensic Image Comparison and Interpretation Evidence: Guidance for Prosecutors and Investigators, 2015-01-16, p. 8 ([Internet, 2023-04-06](https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/405528/Image_Comparison_and_Interpretation_Guidance_Issue_1_160115.pdf))