Citation styles: the official guides
Abschlussbedingungen
Here there are the official guides and some non official but well done guides.
3. Numeric styles (Sciences, Engineering and Medicine)
Stile Vancouver
Citing Medicine, 2. ed.
Citare e fornire riferimenti bibliografici guida di Cecilia Sironi per studenti di infermieristica e non solo
Stile IEEE
The IEEE Guide to Writing in the Engineering and Technical Fields. Appendix: IEEE Style for References
Stile AMA (American Medical Association)
AMA Manual of Style, 11th ed.
AMA 11th Referencing Guide, James Cook university
Stile ACS (American Chemical Society)