There's a filter in Mendeley's research catalog: http://www.mendeley.com/research-papers/search/?query=%22cat+pictures%22 http://www.mendeley.com/research-paper

There's a filter in Mendeley's research catalog: http://www.mendeley.com/research-papers/search/?query=%22cat+pictures%22 http://www.mendeley.com/research-papers/search/?query=%22cat... for showing only open access papers. (disclaimer: my employer)