virtual collections schematic A virtual collection is a coherent set of links to digital objects (e.g. annotated text, video) that can be easily created, accessed and cited.
The links can originate from different archives, hence the term virtual. A virtual collection is suitable for manual access (using a web-browser) as well as automated processing (e.g. by a webservice).

More information can be found on the CLARIN website.

User Manual

Browsing Collections

Click on the "Browse" button in the top menu:
menu browse item

The Virtual Collection Registry home page lists all public collections. For each collection the title, type and creation date are shown.

Available actions:

  • Click the button to view the collection description.
  • Click the collection title to view the complete collection details.
  • Click the button to get the citation details for this collection.

The list of collection can be filtered by clicking the button. This will open the filter options:
menu filter options
After filling in one or more filter options, press the "Filter" button to apply the filter or use the "Clear" button to clear any applied filter.

Citing Collections

Collections can be cited by clicking the icon. This icon is available for each collection in the public list of collections and for individual collections on the collection details page.

Clicking the citation button will show the following dialog providing basic citation information:
virtual collection citation dialog
Please make sure that you use the assigned persistent identier, shown in the Link field, when citing a virtual collection. All public collections have been assigned a persistent identifier.

Creating New Collections

Click on the "Create" button in the top menu:
menu create item

By default the collection editor is shown in simple mode. As listed below, a number of fields editor advanced mode item are not shown in simple mode and will use the assigned default values. If you want to edit these fields you can switch over to advanced mode using the checkbo in the upper right corner: There is also the option to show additional help. If you toggle the checkbox, additional descriptions will be shown inline with the fields.

Each collection has the following fields:

  • A name
  • A description
  • 0 or more keywords
  • 1 or more authors
In advanced mode the following additional fields are available:
  • A type. One of extensional (default) or intensional.
  • A purpose. One of Research, reference (default), sample or future use.
  • A reproducibility. One of intended (default), fluctuating or untended.
  • An optional reproducibility notice, empty by default
Depending on the selected type, a different set of input field will be shown.

For extensional collections 1 or more references must be added. To add a reference a URI (URL or PID) and a title must be supplied. The references will be scanned in the background.

Each reference is marked:

  • with a grey dot ( ) while scanning.
  • with a yellow check () if the URI is valid but is not recognized as a PID.
  • with a green check () if the reference is valid and recognized as a PID.
  • with a red cross () if the URI did not return a valid response. This will prevent you from saving the collection. All references must be valid.

For an intensional collection several fields describing the query must be supplied.

After saving the collection, the collection is assigned the private state. In order to cite this collection or allow other people to find this collection, the collection must be published first. See the next section, Your Collections, on how to publish the newly created collectio.

Managing Your Collections

When logged in, click on the "My Collections" button in the top menu:
menu my collections item

The My Collections page allows you to manage all your collections. This includes both your public and private collections. Private collections will not be listed in the public Browse Collections page. Depending on the collection state different operations are available.

Available operations for collections in public state:

  • Cite collection
  • View collection details
  • Edit collection
Available operations for collections in private state:
  • View collection details
  • Publish collection
  • Edit collection
  • Delete collection
Available operations for collections in error state:
  • Retry publication
  • Delete collection
If you want to have a public collection deleted, please contact one of the administrators. Make sure to include a motivation.

Collection lifecycle:
vcr lifecycle

Technical Documentation

REST service

The Virtual Collection Registry REST service is accessible at (base URL).

Documentation pointers:

  • API documentation is based on the OpenAPI specification and can be found here.
    • OpenAI specification file is availble here.
  • An older version of the documentation, which includes the query language specification, is available here.
  • You can also consult the WADL file.

OAI provider

The Virtual Collection Registry OAI provider offers all published collections as CMDI or Dublin Core metadata over the OAI/PMH protocol. It is accessible at

Integration with external repositories

The Virtual Collection Registry can be integrated into exteran repositories, such as the Virtual Language Observatory, to make it easy to create collections from search results. All technical information required to enable such an integration can be found here on GitHub.