IOPscience: IOP Publishing open access policy

"IOP is committed to providing long-term, sustainable access to quality scientific research for everyone, whilst maintaining high value, trustworthy author and reader services which enhance scientific communication and progress. We offer authors choice by providing both gold open access and green open access options, but we believe that of the two models gold is better, as it provides immediate access to published research with a broad right of re-use under a sustainable financial model. Green open access relies on the maintenance of the existing subscription model as it makes no contribution to the costs of publication ..."