How does the NSDL handle OAI sets?
NSDL can handle sets in terms of harvesting and providing. When NSDL uses OAI to harvest a collection, as many sets as necessary can be used to specify a collection. That is, a collection can be created from multiple sets if need be. When NSDL uses OAI to provide collections, we represent each collection as a separate set, no matter how many sets we harvested initially to create the collection.
