|Identifying HTTP URI||An HTTP URI that provides a scholarly object with a web identity that is intended to be persistent. The intended persistence can be achieved by means of cross-portal infrastructure (e.g. DOI, handle, PURL, W3ID, ...). Typically, an Identifying HTTP URI does not provide content itself but rather redirects to another HTTP URI that does.|
|Repository Stable HTTP URI||An HTTP URI minted by a repository or a portal, and specifically intended to remain stable over time.|
|Entry Page||The page in a publisher's portal where one typically enters when accessing a scholarly publication, usually by following redirects from an Identifying HTTP URI or via a search engine result. In some portals, the Entry Page is the landing page, in others the Entry Page is an HTML version of the publication.|
|Publication Resource||Any web resource that is considered to be an integral part of a publication. Typical scholarly publications have several associated Publication Resources, such as a PDF version of an article, an HTML version of an article, supplementary information in various formats, datasets, etc.|
|Bibliographic Resource||A web resource that describes the publication in a structured manner, for example, using BibTeX or RIS formatting styles.
The resource is available at a URI that supports
|Author Identifying HTTP URI||An HTTP URI that identifies the author of a publication and is intended to be persistent.|
|Author Description Page||A web resource that provides information about an author, for example, a resource that lists an author's scholarly publications and other metadata. This resource either could provide information that is maintained by single publisher or a repository, or it could be a service that provides information by aggregating across repositories.|
Relation Types are generally registered in the IANA Link Relation Registry, which also describes their meaning and links to the specification in which they were originally defined. The Relation Types used for Signposting are repeated below, with reference to the pattern in which they are applied.
|Relation Type||Signposting Pattern||Description|
||Author||The resource that is the target of the link is a web resource that identifies the author of the publication. In the Author pattern, the Identifying HTTP URI, the Entry Page, and the Publication Resource links to the Author of the publication using the |
||Publication Boundary||The resource that is the target of the link is a collection to which the resource that provides the link belongs.
In the Publication Boundary pattern,
the Entry Page is modeled as a collection.
Each Publication Resource link to the Entry Page
||Bibliographic Metadata||The resource that is the target of the link is a description of the resource that provides the link.
In the Bibliographic Metadata pattern, the Entry Page
links to a Bibliographic Resource
||Bibliographic Metadata||The resource that is the target of the link is described by the resource that provides the link.
In the Bibliographic Metadata pattern, a Bibliographic Resource links to the
Entry Page using the
||Publication Boundary||The resource that is the target of the link belongs to a collection,
which is the resource that provides the link. In the Publication Boundary pattern,
the Entry Page is modeled as a collection.
It links to each Publication Resource using the
||Publication Boundary, Identifier||The resource that is the target of the link is the Identifying HTTP URI of the resource that
provides the link. In the Publication Boundary pattern, each Publication Resource links
to the Identifying HTTP URI
||Bibliographic Metadata, Publication Boundary, Resource Type||The resource that is the target of the link indicates the nature of the resource that provides the link,
e.g. whether it is a landing page, a publication, a dataset, ... In the Publication Boundary pattern,
the Entry Page and each Publication Resource
uses a link with the
There is currently no official registry for attributes that can be used on Typed Links. The most common ones are listed in the Web Linking RFC. The attributes that are important for Signposting are listed below, with reference to the pattern in which they are applied.
||Bibliographic Metadata||The resource that is the target of the link provides details about the format of the resource that is the
target of the link, beyond what can be expressed using the
||Bibliographic Metadata, Publication Boundary||The value of the
Currently, there are no MIME types registered to unambiguously identify bibliographic metadata formats
that are commonly used in scholarly communication. And several unregistered MIME types are used to
refer to the same format. For example,
BibTeX is referred to by means of
RIS is referred to by means of
Preferably, MIME types for bibliographic metadata formats should be
But CrossRef, DataCite, and mEDRA have established an interoperable
practice to access bibliographic metadata using content negotiation on the basis
of unregistered MIME types for three formats. Since Signposting is all about
pragmatism it uses these de-facto MIME types for interoperability; they are listed in the below table.
These MIME types are used in
describedby links that point to Bibliographic Resources
and should be expressed by a client in the
Accept HTTP Request header when accessing the URI that is the target
Many other bibliographic formats are in use and many share
application/json as MIME types. In order to distinguish between
formats of a same MIME type, either a dedicated MIME type should be registered
can be used on a
describedby link to clarify the format beyond its MIME type. The former allows for content negotiation for
the format, the latter does not. The below table shows how the
approach can be used for popular XML-based formats.