  As members of the Virgo Collaboration -- one of the large scientific
collaborations that explore the universe of gravitational waves together with
the LIGO Scientific Collaboration and the KAGRA Collaboration -- we became
aware of biased citation practices that exclude Virgo, as well as KAGRA, from
achievements that collectively belong to the wider LIGO/Virgo/KAGRA
Collaboration. Here, we frame these practices in the context of Merton's
Matthew effect, extending the reach of this well studied cognitive bias to
include large international scientific collaborations. We provide qualitative
evidence of its occurrence, displaying the network of links among published
papers in the scientific literature related to Gravitational Wave science. We
note how the keyword LIGO is linked to a much larger number of papers and
variety of subjects than the keyword Virgo. We support these qualitative
observations with a quantitative study based on a year-long monitoring of the
relevant literature, where we scan all new preprints appearing in the arXiv
electronic preprint database. Over the course of one year we identified all
preprints failing to assign due credits to Virgo. As a further step, we
undertook positive actions by asking the authors of problematic papers to
correct them. We also report on a more in-depth investigation which we
performed on problematic preprints that appeared in the first three months of
the period under consideration, checking how frequently their authors reacted
positively to our request and corrected their papers. Finally, we measure the
global impact of papers classified as problematic and observe that, thanks to
the changes implemented in response to our requests, the global impact
(measured as the number of citations of papers which still contain Virgo
visibility issues) was halved. We conclude the paper with general
considerations for future work in a wider perspective.
