Choose an electronic document management system?

Question

Document flow

You need to find an electronic document management system with the following parameters:
- installation on my server, php + mysql (I want to modify + upload data about documents to the site)
- free (desirable)
Are there such products? And in general, who uses what for document flow?
UPD
It is necessary to automate the organization's work with incoming and outgoing documents. First of all, the coordination of draft documents within the organization.

Answer 1

Organizational and administrative document flow. Thank you!

Answer 2

We have DeloPRO at work. But I'm not sure if it's in php...

Answer 3

from free php did not see anything worthy.
From a good open source, there is Alfresco in Java, a very powerful system. There you can configure, if not all, then a lot. And what not to adjust, then add.