This structure is returned as response to SearchRequest inside SearchResult.
Identity of base where this record is stored.
Library string, used for downloading documents from Aleph when you know proper docNumber.
Identificator in Aleph. It is not that much unique as it could be, but with library string, you can fetch documents from Aleph if you know this.
MARC XML source returned from Aleph. Quite complicated stuff.
Parsed .xml to EPublication structure.