Adam, I think any word spelled as an abbreviation needs not only the full stop that is part of the spelling but also the full stop that is part of the MARC end punctuation (thus 250 ## $a 3rd ed..).

The end punctuation of the 250 and 300 tags, for example is MARC and it is separate from the spelling of "ed." or "in." 

If you think about a computer saying here's an RDA record, I want to strip MARC off and mash this data up, the computer would want to remove the last full stop at the end of your 245, 250, and 300, for example. So if you don't include the MARC end punctuation your stripped data would end up being misspelled.

That's how I've been taking this instruction for the "extra" period. It's serving MARC-only  function.

Bobby

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Robert Bothmann
Metadata & Emerging Technologies Librarian
Professor, Library Services
Minnesota State University, Mankato


-----Original Message-----
From: Program for Cooperative Cataloging [mailto:[log in to unmask]] On Behalf Of Yan Liao
Sent: Monday, September 30, 2013 1:02 PM
To: [log in to unmask]
Subject: Re: [PCCLIST] Punctuation at end of 250 field

I agree with your thought. If 250 ends with an abbreviation, no extra period should be added.

-----Original Message-----
From: Program for Cooperative Cataloging [mailto:[log in to unmask]] On Behalf Of Adam L. Schiff
Sent: Saturday, September 28, 2013 7:55 PM
To: [log in to unmask]
Subject: [PCCLIST] Punctuation at end of 250 field

Hi all, I've got a question regarding ending punctuation in the 250 field. 
RDA D.1.2.1 indicates that in ISBD display, an full stop would be added after an edition statement, even if the statement ends in an abbreviation:

3rd ed.. --
not
3rd ed. --

LC-PCC Policy Statement for 1.7.1 says: "If either field 245 or 250 does not end in a period, add one."

Am I correct in my thinking that the implication of this policy statement is that if an edition statement ends in an abbreviation, a second period would NOT be added?  In other words, which of the following is expected in a PCC record?:

250 ## $a 3rd ed..
   or
250 ## $a 3rd ed.

[Note: the examples are predicated on the abbreviation being found and transcribed as is from the resource].

Thanks,

Adam

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Adam L. Schiff
Principal Cataloger
University of Washington Libraries
Box 352900
Seattle, WA 98195-2900
(206) 543-8409
(206) 685-8782 fax
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http://faculty.washington.edu/~aschiff
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