Der all,
I want to know if a journal from the DOAJ required APC.
I plan to use the field "apc": {"currency": "USD", "average_price": 2300}
And my question is about possible changes, from APC to non APC journal and, less importantly, change in the APC amount.
In the last example, is it valid to say "journal has had APC from created_date to last_updated fields", so from 2015 to last February, or you did not track possible change ?
is there a lot of change in DOAJ journals business model (APC to non APC or vice versa) ?
best,
Maxence