...
The item barcode text field can take in multiple item barcodes separated by a comma. However, the barcodes must belong to the same bibliographic record, have the same availability status and belong to the same customer code. This is primarily to facilitate requesting multiple volumes of a Monographic set or multiple issues of a journal/serial. In cases where the item has multiple bibliographic tiles titles (bound-withs), the titles are concatenated and listed together delimited by pipes (||).
...