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    Well-Known System Numbers in the ILL APDU

    • Article Type: General
    • Product: Aleph
    • Product Version: 17.01

    What is the source of and the meaning of the Well-Known-System number?
    010 L $$a2006040506$$c1
    035 L $$aocm62896539$$c6

    Well-Known-System numbers are defined in xxx40/tab/tab_ill_bib_key.
    In the ILLRequest APDU, the item-id structure provides bibliographic details of the desired item.
    One of the item-id elements is system-no.
    In the ILL protocol, system-no is not defined as "ILL-String", but rather as "EXTERNAL". This means that the structure and format of system-no is defined externally (not in the ILL protocol).

    The IPIG (ILL Protocol Implementers Group governs systems interoperability) defined an External Object for use in the system-no element. This object is called IPIG-System-Number. It is described in Annex A.7.1 of the IPIG Profile (
    The official registry of the IPIG-System-Number can be found at

    This is the ASN.1 object specification:
    IPIG-System-Number {1 0 10161 6 1} DEFINITIONS ::=
    IMPORTS System-Id, ILL-String FROM ISO-10161-ILL-1;
    IPIG-system-number::=SEQUENCE OF SEQUENCE
    type CHOICE
    well-known [1]Well-Known-System,
    other [2]System-Id
    database-ID [3]ILL-String OPTIONAL,
    number [4]ILL-String
    library-of-Congress (1),
    bNB (2),
    canadiana (3),
    oCLC (4),
    dialog (5),
    rLIN (6),
    wLN (7),
    cARL (8)

    As shown above, the type element can be either a "system-ID" (aka InstitutionSymbol) indicating the system whose number follows (such as local library system’s internal database ID) or it can be of type "well-known".
    If the type is "well-known", then you have to include the number that identifies the Well-Known-System, such as OCLC or RLIN. OCLC is Well-Known-System number 3. Therefore, this corresponds to the OCLC Well Known No. in the tab_ill_bib_key table.

    Example from WorldCat via ILL
    OCLC Number 53356086 in record results in:
    ILL L $$aIllRequest.ItemId.SystemNo.External.IPIGSystemNo.IPIGNoSeq.IPIGNo.WellKnownSystem$$b3
    ILL L $$aIllRequest.ItemId.SystemNo.External.IPIGSystemNo.IPIGNoSeq.IPIGNo.Number$$b35397863

    ItemId.SystemNo Fields Available in Aleph
    503 IllRequest.ItemId.SystemNo.External.IPIGSystemNo.IPIGNo.Other.PersonOrInstitutionSymbol.Institution
    503 IllRequest.ItemId.SystemNo.External.IPIGSystemNo.IPIGNo.WellKnownSystem
    504 IllRequest.ItemId.SystemNo.External.IPIGSystemNo.IPIGNo.DatabaseId
    505 IllRequest.ItemId.SystemNo.External.IPIGSystemNo.IPIGNo.Number

    From issue resolution:
    1. $$c is not required in 010,035 fields.
    2. It brings unnecessary number at the end of the correct number and therefore locate is not perfomed. tab_filing removes the $$c but not its value.
    3. "Offer a fix_routine to remove the sub-field or remove it from Indexing" - I was unable to find out where from it comes and what it used for. I would remove it at all.

    Additional Information

    In order to try and solve this problem we first need to ‘see’ the problem.
    We were unable to add the 010 or the 035 to the lending request.

    Please see the scenario in the Issue attachment tab (8192-50559 - 20080417.doc) and let us know what we should do to add the 010 and 035 to the lending request.


    • Article last edited: 10/8/2013