From a News Release:
The State Scientific and Technical Library of Ukraine together with the Ministry of Education and Science of Ukraine launched the Open Ukrainian Citation Index (OUCI) http://ouci.dntb.gov.ua/en/ – a search engine [English language interface available] and a database of citations that come from all publishers using the Crossref’s Cited-by service.
This engine supports the Initiative for Open Citations (I4OC) – a collaboration between scholarly publishers, researchers, and other interested parties to promote the unrestricted availability of scholarly citation data.
The OUCI database contains metadata for scientific publications having received their DOI from Crossref, takes into account citations between publications (DOI to DOI) and includes special search filters, such as: year, type of document, title, publisher, indexing in Scopus or Web of Science etc.
Direct to Open Ukrainian Citation Index (OUCI)
Read the Complete Launch Announcement