Even when running a paperless office, the paperwork never ends. You create and process documents on a daily basis. Creating a linkage between relevant documents helps to maintain accurate and transparent information and increases efficiency. If you work with SAP Business One 9.2 or a later version, you know that you can add a reference to a given document, other documents created in SAP Business One or external documents. Now, referenced documents are supported also in inventory documents (goods issue & receipt, inventory transfer, and inventory transfer request), purchase request, checks for payment and recurring postings.
In addition, a number indicating how many documents are referenced to the given document is displayed next to the “Referenced Document” button:
Available in SAP Business One 9.3, version for SAP HANA and SAP Business One 9.3.
Source: Ari Schapira | SAP Business One – The Tip of the Week