 These criticisms prompted librarian Jeffrey Beall to write that in his opinion Nova Science Publishers was in the "bottom-tier" of publishers.A recent survey of national and international databases of scholarly book publishers (including the Book Citation Index, Scopus, CRIStin, JUFO, VIRTA and SPI) identified Nova as one of a "core of publishers that are indexed in all five" of the information systems surveyed.This "core" contained 46 out of the 3,765 publishers identified.