categorizing my bibliography

ecekonuk

Hello,
I'm a PhD student, and I've been using Zotero for a while now. I need to categorize my bibliography as follows:

Bibliography

Primary Resources

Municipality Publications
xxxx
xxxx
xxxx

Newspaper Articles
xxxx
xxxx
xxxx

Secondary Resources

xxxx
xxxx
xxxx

I have been keeping my references in subcategories. However, I couldn't find an appropriate way to make this categorization automatic, as I cite each reference. Could you please help me with this issue?

Many thanks,