Here are two examples

PBCore embedded in Atom

(Accessed through an OpenSearch API)

OpenSearch is an open API for documenting and exposing search query interfaces. Although it supports any data format for query responses, this example uses the Atom format (similar to RSS and compatible with most feed readers), with embedded PBCore records.

The American Archive Content Inventory Project has an OpenSearch interface, which is described at http://americanarchiveinventory.org/catalog/opensearch.xml

You can craft queries that return pbcore metadata by adding content_format=pbcore to the query string. For example, the following URL returns pbcore metadata about items in the CPB collection (assuming you are logged in with appropriate credentials).

http://americanarchiveinventory.org/catalog.atom?content_format=pbcore&forganization_name_facet=Corporation+for+Public+Broadcasting

PBCore accessed through OAI

The OpenArchives Initiative is a collection of APIs and protocols designed to support the harvesting of metadata over the web.

The American Archive Content Inventory Project has an OpenSearch interface. By using the OAI identify verb, you can get basic information about the collection and OAI interface:

http://americanarchiveinventory.org/catalog/oai?verb=Identify

You can retrieve a list of records in the PBCore format by using the listRecords verb along with metadataPrefix=pbcore (assuming you are logged in with appropriate credentials):

http://americanarchiveinventory.org/catalog/oai?verb=ListRecords&metadataPrefix=pbcore