title: Relative mass determination from darkfield electron micrographs with an application to ribosomes.
mesh_terms: D001407:Bacillus / Q000166:cytology; D001412:Bacillus subtilis / Q000166:cytology; D004926:Escherichia coli / Q000166:cytology; D008433:Mathematics; D008722:Methods; D008854:Microscopy, Electron; D012270:Ribosomes; D012542:Scattering, Radiation; D014027:Tobacco Mosaic Virus