1. Very low voltage electron microscopy;Crewe;Ultramicroscopy,1976
2. Low voltage electron microscopy;Nixon,1958
3. Low voltage electron microscope;Wilska,1960
4. Low voltage electron microscope with energy filtering and amplitude contrast;Wilska,1970
5. Determination of the non-localization of the inelastic scattering of electrons by electron microscopy;Isaacson;Optik,1974