Single is misspelled. “Sigle” Is N significant?
Wikipedia says:
The “System for Information on Grey Literature in Europe” (SIGLE) was established in 1980, two years after a seminar on grey literature organised by the European Commission in York (UK). Operated by a network of national information or document supply centres active in collecting and promoting grey literature, SIGLE was an on line, pan-European electronic bibliographic database and document delivery system.
The objective was to provide access to European grey literature and to improve bibliographic coverage.
From 1980 to 1985, SIGLE was funded by the Commission of the European Communities (CEC). When CEC financial support ended in 1985, the national centres formed a network for the acquisition, identification and dissemination of grey literature called “European Association for Grey Literature Exploitation” or EAGLE, who became the producer of the SIGLE database.
Grey literature (or gray literature) are materials and research produced by organizations outside of the traditional commercial or academic publishing and distribution channels.
Good find!
Not sure if it works in this context, but “sigle” is French for “initials” and Italian for “acronym.”