Za dostop do poročil o raziskavah, ki so objavljene v znanstvenih revijah, je treba praviloma plačati. Večini raziskovalcem dostop do objav omogočajo inštitucije, v okviru katerih delujejo, a ker so naročnine na znanstvene revije zelo drage, velikokrat vsi nimajo dostopa do vse literature.
Pravkar objavljena razširitev za brskalnike imenovana Unpaywall, kar sama poišče pdf članka, do katerega na strani revije morda nimamo dostopa. Za razliko od “piratskih” orodij kot je Sci-Hub, Unpaywall podaja povezave zgolj do verzij člankov, ki so jih lahko kje drugje na spletu najdemo v prostem dostopu.
At its heart, Unpaywall provides a simple interface into a database of digital object identifiers (DOIs) — some 86 million in all. In October 2016, Priem and co-inventor Heather Piwowar, who together founded the not-for-profit company Impactstory in Vancouver, Canada, launched oaDOI, an ‘application programming interface’ (API), or set of programmatic instructions, that allows researchers to search that database for papers on the basis of their DOI. oaDOI is used more than a million times per week, according to Priem; it successfully finds an open-access version of a paper around 30% of the time. Unpaywall basically queries that same database automatically, flagging articles for which a free version is available.
oaDOI, in turn, draws inspiration from DOAI (Digital Open Access Identifier), says Priem. DOAI is described on its homepage as an “alternate DOI resolver” that redirects requests to the free version of an article, if available, and otherwise to the paywalled paper itself.
According to Piwowar, both oaDOI and Unpaywall include a nimble title-matching feature, which uses an algorithm to compare titles, forgiving spacing and punctuation differences. The idea is to overcome the fact that titles change in different versions of manuscripts, she explains. (Vir: Unpaywall finds free versions of paywalled papers : Nature News & Comment)
