Eric, You might want to look at ISO 2709 - the standard giving the format underlying MARC records. It allows alpha values for the tags. But MARC does not allow alpha values. Wikipedia give a brief summary, although the ISO standard is only 6 pages long. Peter Noerr > -----Original Message----- > From: Code for Libraries [mailto:[log in to unmask]] On Behalf Of > Eric Lease Morgan > Sent: Wednesday, June 25, 2008 12:21 PM > To: [log in to unmask] > Subject: [CODE4LIB] alpha characters used for field names > > Are alpha characters used for field names valid in MARC records? > > When we do dumps of MARC records our ILS often dumps them with FMT and > CAT field names. So not only do I have glorious 246 fields and 100 > fields but I also have CAT fields and FMT fields. Are these features > of my ILS -- extensions of the standard -- or really a part of MARC? > Moreover, does something like Marc4J or MARC::Batch and friends deal > with these alpha field names correctly? > > -- > Eric Lease Morgan