Gray literature (or grey literature) is a field in library and information science. The term is used variably by the intellectual community, librarians, and medical and research professionals to refer to a body of materials that cannot be found easily through conventional channels such as publishers, "but which is frequently original and usually recent" in the words of M.C. Debachere.[1] Examples of grey literature include technical reports from government agencies or scientific research groups, working papers from research groups or committees, white papers, or preprints. The term grey literature is often employed exclusively with scientific research in mind. Nevertheless, grey literature is not a specific genre of document, but a specific, non-commercial means of disseminating information.
The identification and acquisition of grey literature poses difficulties for librarians and other information professionals for several reasons. Generally, grey literature lacks strict bibliographic control, meaning that basic information such as author, publication date or publishing body may not be easily discerned. Similarly, non-professional layouts and formats and low print runs of grey literature make the organized collection of such publications challenging compared to more traditional published media such as journals and books.[2]
Information and research professionals generally draw a distinction between ephemera and grey literature. However, there are certain overlaps between the two media and they certainly share common frustrations such as bibliographic control issues.
Contents |
The concept of grey literature is historical. Some decades ago the term grey literature did not exist as a category although what is considered grey today was among the existant literature. When Butterworths published the first edition of Charles P. Auger’s landmark work on grey literature in 1975, paradoxically neither the summary nor the index mentioned this term. The book was just about reports literature (Auger, 1975)[3]. Despite the absence of a label, Auger described the nature of this “vast body of documents” in a way that would later characterize grey literature, referring to its “continuing increasing quantity”, the “difficulty it presents to the librarian”, its ambiguity between temporary character and durability, and its growing impact on scientific production. He also pointed out the “number of advantages over other means of dissemination, including greater speed, greater flexibility and the opportunity to go into considerable detail if necessary”. For Auger, reports were a “half-published” communication medium with a “complex interrelationship (to) scientific journals”.
“Semi-published literature” is a connotation of grey literature (Keenan, 1996)[4]. But it reminds, too, that one can speak about reports without a generic concept. Auger promoted the term of “grey literature” only in the 2nd edition of his book (Auger, 1989)[2]. Since then, the meaning of “GL” remained a challenge to scientists and librarians. Does “GL” make sense? Is it necessary? Is it (still) helpful for the study and processing of scientific literature? Or using a variation on the famous quote from Dorothy L. Sayers, will it “run away (…) like cows if you look (it) in the face hard enough”?
There are several definitions of grey literature, the most common being the so-called “Luxembourg definition,” which was discussed and approved during the Third International Conference on Grey Literature in 1997: “[Grey literature is] that which is produced on all levels of government, academics, business and industry in print and electronic formats, but which is not controlled by commercial publishers.” In 2004, at the Sixth Conference in New York, a postscript was added for purposes of clarification “...not controlled by commercial publishers, i.e., where publishing is not the primary activity of the producing body” (see Schöpfel & Farace, 2010)[5].
The Luxemburg definition accentuates the supply side of grey literature, e.g., its production and publication both in print and electronic formats. It calls attention to the question of dissemination, the difficulty to identify and access documents described as ephemeral, non-conventional or underground.
Material that “may not enter normal channels or systems of publication, distribution, bibliographic control, or acquisition by booksellers or subscription agents” (U.S. Interagency Gray Literature Working Group): this concept meets Mackenzie Owen’s observation that “grey does not imply any qualification (but) is merely a characterization of the distribution mode” (1997)[6].
Internet transforms the whole value chain of publishing. The Web offers new tools and channels for producing, disseminating and assessing scientific literature. Author and reader, producer and consumer change their information behaviour. We definitely left the Gutenberg era. So what about the definition of grey literature? Is it still empirically sound?
The definition of grey literature is also an economic definition. With the changing research environment and new channels of scientific communication, it becomes clear that grey literature needs a new conceptual framework.[7]
The Grey Literature Network Service defines grey literature as "information produced on all levels of government, academics, business and industry in electronic and print formats not controlled by commercial publishing i.e. where publishing is not the primary activity of the producing body." (Luxembourg, 1997 - Expanded in New York, 2004).[8]
The U.S. Interagency Gray Literature Working Group (IGLWG) "Gray Information Functional Plan," 18 January 1995, defines grey literature as "foreign or domestic open source material that usually is available through specialized channels and may not enter normal channels or systems of publication, distribution, bibliographic control, or acquisition by booksellers or subscription agents."
The 12th International Conference on Grey Literature at Prague in December 2010 discussed a new approach to grey literature. The current definition of grey literature – the New York definition – remains helpful and should not be replaced but adapted to the changing environment.
The typological approach doesn’t provide an exhaustive and explicit list of items. The economic approach of the New York definition, on the other hand, is intensional and specifies the necessary condition for a document being part of the grey literature. But the same definition is not sufficient in the context of Internet publishing, and we need to designate more essential attributes to clearly differentiate grey from other items.
The proposal is to add four attributes to the New York definition:
The proposal for a new definition ("Prague Definition") of grey literature is as follows:
"Grey literature stands for manifold document types produced on all levels of government, academics, business and industry in print and electronic formats that are protected by intellectual property rights, of sufficient quality to be collected and preserved by library holdings or institutional repositories, but not controlled by commercial publishers i.e., where publishing is not the primary activity of the producing body."
Grey literature includes all kind of quality or seminal documentary material a library would like to collect but can’t easily because of non-conventional distribution channels. It is not (only) a question of production and dissemination but (also) of quality and collection. Without (inter)mediation by libraries, no grey literature. It is a case for LIS professionals, a challenge that brings together the communities of grey literature and special collections.
A couple of years ago, the main problem with grey literature appeared to be economics. Simpson (1995)[10] observed, "peripheral materials, including grey literature, expand unabated. Libraries having difficulty collecting traditional materials have little hope of acquiring the periphery."
Today, due to the overwhelming success of web publishing and access to documents the focus has shifted to quality, intellectual property and (inter)mediation. Without a revision that includes the mentioned attributes, the current definition risks being increasingly unable to differentiate grey from other documents.
The proposal for a revised “Prague definition” brings together the former economic approach with new attributes. The next step should be to check this definition against common usage in libraries and different types of grey and other documents. Once done, the value of the definition can be evaluated on the basis of the answers to the following two questions: does this new definition include all kind of documents usually considered by LIS professionals as grey literature, including today’s difficult-to-process and hard-to-collect items, and does it lead to further differentiation or better understanding of how grey literature may be distinguished from other forms of literature? Three challenges in particular are said to face professionals in the field at the present moment:
With reference to grey literature, replies to a survey in 2010 stated “(…) it is important for knowledge” and “it is a question of freedom” or “non-mainstream publishing”. The future will show if the concept of grey literature remains “ephemeral” and if it contributes to better understanding and processing of this special part of scientific and technical information.
The term traditionally referred to reports, conference proceedings and doctoral theses. In the OpenSIGLE repository, reports are the most numerous among the different types of grey literature. The ‘reports’ category covers a wide variety of very different documents: institutional reports, annual or activity reports, project or study reports, technical reports, reports published by ministries, laboratories or research teams, etc. Some are disseminated by national and international public bodies; others are confidential, protected, or disseminated to a restricted readership, such as technical reports from industrial R&D laboratories. Some are voluminous, with statistical appendices, while others are only a few pages in length.
In the other categories, citation analyses[12] offer a wide range of grey resources. Besides theses and conference proceedings, they also include unpublished manuscripts, newsletters, recommendations and technical standards, patents, technical notes, product catalogs, data and statistics, presentations, malin-grey literature, personal communications, working papers, house journals, laboratory research books, preprints, academic courseware, lecture notes, and so on. The international network GreyNet maintains an online listing of document types.
The internet is altering the landscape, not only by changing user behaviour, but also, and especially, because more and more grey and malin-grey literature is being published on the Web. The internet has radically changed access and distribution methods, accentuating the ephemeral and volatile nature of grey literature, and is set to become the major area for grey literature research in the years ahead.
Malin-grey literature has long intrigued grey literature researchers in representing the nexus of an exclusive view of intended readership, and publishing in its most paradoxical and internally self-contradictory aspect. By contrast with grey literature writ large, 'malin-grey literature' refers to publications whose construction and self-referencing are actively construed to avoid the attention of information professionals. Typically such professionals employ various parameters in identifying which publications are suited to incorporation within a particular collection. To avoid dissemination and archiving the authors of malin-grey literature employ the absence of bibliographical indicators, deception, disinformation, rapid decomposition (or other self-destructive construction), obscurity or atypical formats. Malin-grey literature should not be confused with samizdat or underground literature per se, as these publications often are only concerned with disguising the author and distributor's identities, not actively preventing dissemination.[13]
Some commentators have suggested that the name derives from the French for 'deceptive ingenuity', others - less convincingly - that it is a reference to the Anne-Marie Malingrey (fl. 1960s-70s), a French historian.[14][15]
Grey literature has a role of its own as a means of distributing scientific and technical information[16]. Professionals insist on its importance for two main reasons: research results are often more detailed in reports, doctoral theses and conference proceedings than in journals, and they are distributed in these forms up to 12 or even 18 months before being published elsewhere[17]. Some results simply are not published anywhere else.
A Franco-Dutch study reviews 64 citation analyses published between 1987 and 2005, citing altogether several thousand references[12][18]. The table below shows the proportion of grey literature cited in publications from different scientific disciplines.
| Field | Grey literature citations (in %) |
|---|---|
| Soil sciences | 14% |
| Biology | 5-13% |
| Veterinary medicine | 6% |
| Psychiatry (addiction | 1% |
| Psychology | 3% |
| Engineering sciences | 39-42% |
| Economic sciences | 9-17% |
| Sociology | 7-9% |
| Education sciences | 14-19% |
The relative importance of grey literature is largely dependent on research disciplines and subjects, on methodological approaches, and on sources used. In some fields, especially the life sciences and medical sciences, there has been a traditional preference for conventional distribution media (journals), while in others, such as agriculture, aeronautics and the engineering sciences in general, grey literature resources tend to predominate.
In particular, public administrations and public and industrial research laboratories produce a great deal of “grey” material, often for internal and in some cases “restricted” dissemination[19].
Following another study[20], grey literature seems also to play a considerable part in the library and information sciences, accounting on average around 20% of all sources used a figure that may be compared with the citation habits in economics and educational sciences. Even so, citations to grey material vary widely between different papers from 0% to 50% and more, depending on subject areas and methodologies.
The Grey Literature International Steering Committee (GLISC) was established in 2006 after the 7th International Conference on Grey Literature (GL7) held in Nancy (France) on 5–6 December 2005.
During this conference, the Istituto Superiore di Sanità (ISS) (Rome, Italy) presented guidelines for the production of scientific and technical reports included in the wider category of grey literature. The Italian initiative for the adoption of uniform requirements for the production of reports was discussed during a Round Table on Quality Assessment by a small group of GL producers, librarians and information professionals who agreed to collaborate in the revision of the guidelines proposed by ISS. The group approving these guidelines – informally known as the “Nancy Group” – has been formally defined as the Grey Literature International Steering Committee (GLISC).
The Guidelines include ethical principles related to the process of evaluating, improving, and making reports available and the relationships between GL producers and authors. The latter sections address the more technical aspects of preparing and submitting reports. GLISC believes the entire document is relevant to the concerns of both authors and GL producers.
Since 1993, GreyNet International, the Grey Literature Network Service, organizes the International Conferences Series on Grey Literature, producing a substantial body of scientific and professional papers on grey literature:
Currently, the conference papers from GL1 to GL12 are openly available in the OpenGrey Repository, http://www.opengrey.eu
GreyNet also organizes GreyWorks the Summer Workshop Series on Grey Literature:
GreyNet likewise publishes the only international scientific journal on grey literature, The Grey Journal (ISSN print 1574-1796, ISSN e-print 1574-180X). The Grey Journal appears three times a year - in spring, summer, and autumn. Each issue in a volume is thematic and deals with one or more related topics in the field of grey literature. The Grey Journal appears both in print and electronic formats. The electronic version on article level is available via EBSCO’s LISTA-FT Database (EBSCO Publishing). The Grey Journal is indexed by the Scopus database and other A&I services.
The Grey Journal, International Journal on Grey Literature:
In the ongoing discussion on new business models of academic publishing, eScience and open access to public research results, non-commercial distribution channels will continue to play a central role as vectors of scientific communication, alongside commercial publishing.
Scientists ask for trustworthy information. The ClimateGate discussion showed that the question of quality needs attention. Of course, one part of grey literature has some kind of quality label (Ph.D. jury, scientific committee selection of communications etc.). What about the rest? How can libraries guarantee high quality for grey items? Can they? Will Web2.0 item tagging become an alternative to review and selection?
Another question is about impact and usage. In the past, impact metrics were limited to citations and journals. Today, usage metrics offer new opportunities to measure impact of a large scale of digital resources, also on the individual item level. Tomorrow, these metrics will provide additional information on quality and popularity to the end user.
Open archives will offer more appropriate services and functions for at least some segments of grey literature if not for all. But bibliographic control of grey literature will remain problematic despite the trend toward standardization of digital documents. And the libraries, together with their scientific communities, need to find new forms for the fundamental functions of scientific publishing, applied to open repositories, non-commercial items and datasets.