Alkaline paper and MARC format records

I just saw Barbara's question about recording information in the USMARC
format regarding the use of alkaline paper.  Ed Glazier, the quality
control officer here at RLG tells me that there is no place currently
where this designation MUST be recorded. However, LC and others are
putting this in the 020 immediately following the ISBN.  Note that this
practice is probably (not certainly) based on a transcription of the
ISBN when it includes the alkaline paper information at the end; keep in
mind that not ALL materials printed on alkaline paper are so designated,
even if they show the infinity symbol.

The 020 looks like this:

       020   $a0275938271 (alk. paper)";

With format integration not too far away, this practice may well change.
Ed suggested that the 037 field (Subfield f, "form of issue") ,
currently "Stock Number" but slated to change to "Source of
Acquisition", may be a likely spot.

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                  Conservation DistList Instance 4:40
                 Distributed: Sunday, January 27, 1991
                        Message Id: cdl-4-40-001
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