Authors: Nuno Freire ^1,2; Pável Calado ^3,4; Bruno Martins ^1,2

• 1 Universidade de Lisboa = University of Lisbon
• 2 Universidade de Lisboa = University of Lisbon = Université de Lisbonne
• 3 Instituto Superior Técnico, Universidade Técnica de Lisboa [IST / Técnico Lisboa]
• 4 Instituto Superior Técnico [IST / Técnico Lisboa]

In the World Wide Web, a very large number of resources is made available through digital libraries. The existence of many individual digital libraries, maintained by different organizations, brings challenges to the discoverability, sharing and reuse of the resources. A widely-used approach is metadata aggregation, where centralized efforts like Europeana facilitate the discoverability and use of the resources by collecting their associated metadata. The cultural heritage domain embraced the aggregation approach while, at the same time, the technological landscape kept evolving. Nowadays, cultural heritage institutions are increasingly applying technologies designed for the wider interoperability on the Web. This paper presents a study of the current application by cultural heritage data providers of technological solutions in use for making structured metadata available for re-use in the Internet. We investigated the use of both linked data and technologies related with indexing of resources by Internet search engines. We have conducted a harvesting experiment of the landing pages from websites of digital libraries that participate in Europeana, and collected statistics about the usage these particular technologies. These technologies allow for representing structured data within HTML, or for structured data to be referred to by links within HTML or through HTTP headers capabilities. We conclude with a discussion of future work for establishing a solution for cultural heritage aggregation based on the current situation and the available technologies.