Professional associations and nonprofit organizations can be great sources of information and research albeit not peer-reviewed. Many nonprofit organizations freely make their research and publications available and whereas most associations provide services and information to members only, many allow access to some information with free online registration.
Canadian Co-operative Research Network offers a free online co-op research portal with a searchable online co-op research library (1350+ publications); news of scholarships, conferences, publication opportunities and lots more. The library's portal is on Zotero
Hosted from Mount Saint Vincent University, SE Space, "collects digital documents on co-operatives and the wider social economy" in Canada.