Classificazione LCHV8079.55
⮑ HV1-9960. Social pathology. Social and public welfare.
⮑ HV7231-9960. Criminal justice administration
⮑ HV7551-8280.7. Police. Detectves. Constabulary
⮑ HV8031-8080. Police duty. Methods of protection
⮑ HV8079.5-8079.55. Traffic control. Traffic accident