Hi, According to that SSAP spec(v1.02 p37), "Dataset.Collection is the registered IVOA identifer of the data collection to which the dataset belongs, e.g., "ivo://sdss/dr5/spec"". Does this imply that in order to publish a spectral data archive using SSAP, one must register the data archive first in the registry as resourceType = Data Collection? Greetings, Jaiwon