  The need for open scientific knowledge graphs is ever increasing. While there
are large repositories of open access articles and free publication indexes,
there are still few free knowledge graphs exposing citation networks, and often
their coverage is partial. Consequently, most evaluation processes based on
citation counts rely on commercial citation databases. Things are changing
thanks to the Initiative for Open Citations (I4OC, https://i4oc.org) and the
Initiative for Open Abstracts (I4OA, https://i4oa.org), whose goal is to
campaign for scholarly publishers to open the reference lists and the other
metadata of their articles. This paper investigates the growth of the open
bibliographic metadata and open citations in two scientific knowledge graphs,
OpenCitations' COCI and Crossref, with an experiment on the Italian National
Scientific Qualification (NSQ), the National process for University Professor
qualification which uses data from commercial indexes. We simulated the
procedure by only using such open data and explored similarities and
differences with the official results. The outcomes of the experiment show that
the amount of open bibliographic metadata and open citation data currently
available in the two scientific knowledge graphs adopted is not yet enough for
obtaining results similar to those provided using commercial databases.
