3. Arms, W., Dushay, N., Fulker, D., Lagoze, C.: A case study in metadata harvesting: the NSDL. Library Hi Tech 21, no. 2, 228–237 (2003). doi:10.1108/07378830310479866
4. Lagoze, C., Krafft, D., Cornwell, T., Dushay, N., Eckstrom, D., Saylor, J.: Metadata aggregation and “automated digital libraries”: a retrospective on the NSDL experience. Proceedings of the 6th ACM/IEEE-CS Joint Conference on Digital libraries 230–239 (2006). doi:10.1145/1141753.1141804
5. Bruce, T., Hillmann, D.: The Continuum of Metadata Quality: Defining, Expressing, Exploiting. In: Hillmann, D., Westbrooks, E., (eds.), Metadata in Practice, pp. 238–256. ALA, Chicago (2004).
14.
Functional Requirements for Bibliographic Records: Final Report. IFLA Study Group on the Functional Requirements for Bibliographic Records. (UBCIM Publications, New Series; v. 19). München: K.G. Saur, (1998).
http://www.ifla.org/VII/s13/frbr/frbr.htm