I chose to publish the proceedings of Downscale2016 using Figshare. This gives a nice persistent place for the proceedings and includes a DOI. To cite the proceedings, use the text below. The proceedings is published using the CC-BY license.
Victor de Boer, Anna Bon, Cheah WaiShiang and Nana Baah Gyan (eds.) Proceedings of the 4th Workshop on Downscaling the Semantic Web (Downscale2016). Co-located with the 4th International Conference on ICT for Sustainability (ICT4S) Sep 1, 2016, Amsterdam, The Netherlands. doi:10.6084/m9.figshare.3827052.v1