In a series of emails
Chris Freeland,
David Shorthouse, and I have been discussing DOIs in the context of the Biodiversity Heritage Library (BHL). I thought it worthwhile to capture some thoughts here.
In an email Chris wrote:
Sure, DOIs have been around for a while, but how many nomenclators or species databases record them? Few, from what I've seen - instead they record citations in traditional text form. I'm trying to find the middle ground between guys like the two of you, who want machine-readable lit (RDF), and most everyone else I talk with, including regular users of Botanicus & BHL, who want human-readable lit (PDF). I'm not overstating - it really does break down into these 2 camps (for now), with much more weight over on the PDF side (again, for now).
I think the perception that there are two "camps" is unfortunate. I guess for a working taxonomist, it would be great if for a given taxonomic name there was a way to see the original publication of the name, even if it is simply a bitmap image (such as a JPEG). Hence, a database that links names to images of text would be a useful resource. If this is what BHL is aiming for, then I agree, DOIs may seem to be of little use, apart from being one way to address the issue of persistent identifiers.
But it seems to me that there are lots of tasks for which DOIs (or more precisely, the infrastructure underlying them) can help. For example, given a bibliographic citation such as
Fiers, F. and T. M. Iliffe (2000)
Nitocrellopsis texana n. sp. from central TX (U.S.A.) and
N. ahaggarensis n. sp. from the central Algerian Sahara (Copepoda, Harpacticoida). Hydrobiologia, 418:81-97.
how do I find a digital version of this article? Given this citation
Fiers, F. & T. M. Iliffe (2000). Hydrobiologia, 418:81.
how do I decide that this is the same article? If I want to see whether somebody has cited this paper (and perhaps changed the name of the copepod) how do I do that? If I want follow up the references in this paper, how do I do that?
These are the kinds of thing that DOIs address. This article has the DOI
doi:10.1023/A:1003892200897. This gives me a globally unique identifier for the article. The DOI foundation provides a resolver whereby I can go to a site that will provide me with access (albeit possibly for a fee) to the article. CrossRef provides an OpenURL service whereby I can
- Retrieve metadata about the article given the DOI
- Given metadata I can search for a DOI
To an end user much of this is irrelevant, but to people building the links between taxonomic names and taxonomic literature, these are pressing issues. Previously I've given some examples before where taxonomic databases such as
Cataloggue of Life and
ITIS store only text citations, not identifiers (such as DOIs or Handles). As a result, the user has to search for each paper "by hand". Surely in an ideal world there would be a link to the publication? If so, how do we get there? How do IPNI, Index Fungorum, ITIS, Sp2000, ZooBank, and so on link their names and references to digitised content? This is where a CrossRef-style infrastructure comes in.
Publishers "get this". Given the nature of the web where users expect to be able follow links, CrossRef deals with the issue of converting the literature cited section of a paper into a set of clickable links. Don't we want the same thing for our databases of taxonomic names? And, don't we want this for our taxonomic literature?
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It is worth noting that the perception that DOIs only cover modern literature is erroneous. For example, here's the description of
Megalania prisca Owen (
doi:10.1098/rstl.1859.0002), which was published in 1859. The Royal Society of London has DOIs for articles published in the 18th century.
If the Royal Society can do this, why can't BHL?