Supplemental Issues
Issues with Special Titles
Index Issues
a. Supplemental Issues: A volume may have an issue that is "extra," that falls outside of the normal publication pattern. Often the publisher will call it a "supplement." Since we are trying to reproduce the print version, we want to make sure we accurately reflect the order in which these issues were published. Check the frontmatter of all issues that are available to you for the volume in hand when you receive a supplemental issue to be published. A supplement could come in the middle of the volume, or even at the beginning. Do not assume it belongs at the end. Sometimes the supplemental issue will be given the volume number designation, sometimes not. Use the available information on the issue's .pdf's to determine what the enumeration and chronology should be.
Example: The supplemental issue in this example comes before the first numbered issue of the volume. This order was determined by information on the publisher's own website; the issues had been published online by the publisher and the supplemental issue had been given an earlier date of publication than the first numbered issue. As you will see in the images below, there was no date on the supplemental issue itself.
Here is the enumeration and chronology information as it appeared on the supplemental issue:
There is no clue as to the date of publication, other than a copyright statement at the top right corner of the page (not shown here). The only other clue given in the entire issue was the date on the editor's signature, at the end of the preface. (See below.) If the information had not been given on the publisher's website, the signature date might have been used.
The issue data for this supplemental issue should be rendered in the .xml file in the following way. (See below) Note that the issue is given and issue number of "0" and that the word "Supplement" takes the place of an issue number in the issue_identifier and the issue_title:
b. Issues with Special Titles: There can be issues of a journal title which have their own, special title for a particular issue. Rather than ignore the existence of this issue title, we must encode it in the .xml so that it will be properly displayed on the Euclid website. Below is an example of the proper encoding for such a title. Note that the issue_identifier in the header should contain the journal title, NOT the special issue title.

c. Index Issues: Sometimes the entire issue is an index, with no articles at all. These general indices may cover several volumes or a single volume.
Example from BAMS: This example is a General Index for several volumes of the journal Bulletin of the American Mathematical Society. This particular issue has been divided into sections for the different article types that were published in the volumes.
As it appears in Euclid:
The .xml encoding for this display is shown below. Note that each <record> is given a type of "index", and note the differences in the content of the <issue_identifier> and the <issue_title>. This issue is also unusual in that it is "part 2" of volume 3, number 1. This is reflected in the encoding of the <issue_number> element as well as the <issue_identifier>, and the <issue_sortList_title>.