Free Primary Sources:,, and the Magic of Metadata Harvesters

This post is a summary of a presentation given at the 2015 ILAGO Summit in Hood River, Oregon.

DP.LA and have become my go-to tools for primary source materials. Metadata harvesters (this is the fancy name for the kind of tool that and are) are amazingly useful, fun to explore, and rely on open content and sharing in a way that warms my cold librarian heart. I gave a presentation on these tools at the ILAGO (Information Literacy Group of Oregon) Summit and I wanted to share it with you all. Here is my slide deck, followed by a brief synopsis for my fellow preferrers of text.

I have three goals for this talk. First, I want all of you to be able to go back to your libraries and share how rich, deep, and amazing the content available through metadata harvesters is. That’s the key point: metadata harvesters are really freaking cool. Once we’ve established that, I want you all to be able to explain to your coworkers what underlying technologies and standards are behind the magic of metadata harvesters. Finally, I want to close on the question of how to integrate metadata harvesters into our existing suites of tools for discovery and reference.

Metadata harvesters are really freaking cool.

Showing off the and is easy. It’s pretty easy to manipulate the interfaces and both tools do an adequate job of helping novice searchers. Let’s use an example to see how searching metadata harvesters work. Here’s the scenario: a student comes to the library with an assignment to find primary source materials on a historical figure represented in current popular culture. This student is interested in the Cercei Lannister character on HBO’s Game of Thrones series, so we are looking for primary sources about her historical inspiration Margaret of Anjou. Searching for Margaret of Anjou, including alternate spellings, returns quite a few interesting primary and secondary sources in My favorite is a letter she wrote using veiled language to threaten people who were molesting tenants under her protection. The ease of finding materials really shows off the power and usefulness of metadata harversters like and

Standards and technologies behind the magic

Turning to the underlying technology & standards that enable metadata harvesters to work, we’ll see that Dublin Core, XML, and RDF are foundational technologies. Metadata harvesters like and rely on dublin core and rdf to build standards. The key concept is that the metadata harvesters publish a standard that digital archives can use. Digital archives that wish to share their metadata must publish their metadata using these standards. Then this metadata will harvested and become discoverable. It is important to note that the digital objects themselves are not harvested and remain on the hosting archives’ servers.

Integrating metadata harvesters into our discovery tools

How we can make the amazing sources and resources that are discoverable through metadata harvesters available to our library users? At WSU Vancouver, we make them available through a Libguide. Reflecting on this, I’m starting to be concerned how free sources are largely segregated (made available to students in a different place) from the sources we pay to get access to. Are there strategies we can use to close this gap? It may also be useful to discuss the similarities between library discovery layers and metadata harvesters. Both can make use of the same underlying technology, OAI-PMH, but in my limited experience, the tool built on open standards and sharing is much more successful at providing discovery than the proprietary solutions.

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Free Primary Sources:,, and the Magic of Metadata Harvesters
Linked open data is making huge strides in providing access to primary source materials. The digital holdings of a massive number of galleries, archives, libraries, and museums are now freely accessible. Expensive subscriptions or access to research-level collections are not needed to access a wealth of digital items unavailable just a few years ago. This presentation will demonstrate the amazing things available through metadata harvesters such as and, provide navigation tips for finding primary source materials, and describe the core metadata protocol and technology that makes the magic possible.

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