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Grab your book and scan the ISBN barcode into the general search bar in Connexion. You may get a list of results, in that case it may be easiest to sort them by language to see what you have. Generally, if the is a LOC record (indicated by the D in the L field) that is most likely the best record. If there is no LOC record, check each eng one and see which one has the most holdings and is the most complete. Ebooks may show up in this seach, so make sure you are working with the print record. Now that our holdings are being matched up in OCLC, you may see that the record is listed as being Held by us. This may not always be on the best record. If you decide that the held record is not the best record/match then you will need to follow the instructions linked below for maintaining our holdings correctly.
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Comparing book in hand with Connexion records, start with your title page and then the verso of title page or colophon in the back.
Most books will be straight forward, but it is good to be familiar with the major differences between books and records to know when a record is a match or if a new record is needed: https://www.oclc.org/bibformats/en/input.html
If the publisher is different from what is on the title page, but still matches a different "level" of the publisher that is included in the publication statement on tp verso or colophon, it may have just been a poor choice of publisher by the cataloger as opposed to a different edition of the book.(In colophon above, someone may have used Roaring Brook Press or even Holtzbrinck Publishing Holdings Limited Partnership.) Further investigation may be needed. If the publisher does not match at all, you need to find another record or create a new one as that is a major difference.
If you are working with a first edition and the record does not specifically state "first edition" that is not considered a different book, as it may have just been left off the record. If there is any other edition statement that is in your book but not indicated on the record, you will need to find another record or create a new one. If a record has any other edition statement besides a first edition and your book does not, then you need a different or new record. Different printings of an edition should all be on the same record for that edition, unless the printing statement indicates a revision or updating has occurred. (You can record any general printing statements in the Alma holding record in field 562 $$c.)
If there is a difference in page numbers greater than 3 pages, then a different or new record is most likely needed. If there is a difference in the height of the book, greater than 2 cm, then a different or new record is most likely needed.
Checking uncontrolled and controlled names in Connexion records
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