The content of individual bibliographic entries is © their respective authors and publishers.
My aggregation of collections of entries and their metadata is placed under the CC0 1.0 Universal (CC0 1.0) Public Domain Dedication. Some of the aggregation was done by others, notably Tilman Bayer and Dario Taraborelli as part of their work on the Wikimedia Research Newsletter and the WikiResearch Zotero library. As far as I know, they have not asserted any copyright on that work.