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However, Institutions typically receive MARC data in .mrc or .out (Millennium) formats from Library Management Systems (LMS). This can be converted to MARCXML format with help of third-party tools such as MARCEdit for Windows, YAZ for Linux or other tools recommended by Library of Congress. The Institution should ensure the integrity of data so converted as certain tools are known to mess data owing to encoding problems (A version of YAZ always ignored or replaced diacritic characters).
Holdings and Items data
The 9XX fields are earmarked for institution specific data in MARC and this is widely leveraged by LMS to carry Item and Holding information during extract.