List of military headstamps - Wikipedia
Identification of bullets and cartridge cases (FSC)
PPT - Firearms Identification PowerPoint Presentation, free
(Laboratory Imaging s.r.o.)
A fired bullet and cartridge case
105 mm cartridge case - Identification - General Ammunition Discussion - International Ammunition Association Web Forum
WW2 German, Soviet, Allied militaria, uniforms, awards, weapons history. War relics forum
Large calibre markings (The Western Front Museum)
Introduction to Forensic Science and Criminology → Module 4
NIST Ballistics Toolmark Database
Frequently Asked Questions in Forensic Ballistics, PDF, Caliber