“…Moreover, if the paid article does have an abstract and it has taken an interest of a scientist, this increases the probability that the scientist will pay a fee for accessing and downloading the article. And more disappointing is when a database, like PubMed® (Fig 1) 24 or Scopus® (Fig 2A ), 25 contains the title of the article, but neither its summary/ abstract nor a direct link to the article itself 26 . Such cases disappoint the seeker and decrease the probability that reader will pay to read that closed paper.…”