Christian Fuchs and Marisol Sandoval have published "The Diamond Model of Open Access Publishing: Why Policy Makers, Scholars, Universities, Libraries, Labour Unions and the Publishing World Need to Take Non-Commercial, Non-Profit Open Access Serious" in tripleC: Communication, Capitalism & Critique: Open Access Journal for a Global Sustainable Information Society.
Here's an excerpt:
In the Diamond Open Access Model, not-for-profit, non-commercial organizations, associations or networks publish material that is made available online in digital format, is free of charge for readers and authors and does not allow commercial and for-profit re-use.
The fact that Diamond Open Access (DOA) has a digital format does not hinder that it is also made available in the form of printed publications in addition. We consider it as part of the model that publishers can charge for the actual printing costs without making monetary profits, but provide the digital version without charges. Publication "free of charge" means that neither authors nor individual readers nor institutions such as libraries have to pay for obtaining access to the literature published under the Diamond Open Access Model. Also authors or their institutions do not have to pay publication fees, article processing charges or other fees for getting articles published.
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