...

The OFBiz Data Model was mainly developed using the entity designs from these books. Although OFBiz uses a variation on these models, these books are an excellent reference and design guide for handling business related data. Most of the concepts described are actively used, enough so that it very worthwhile to buy at least the first volume (Volume 1) of this collection.

.

...

Learning

"Apache OFBiz Development: The Beginner's Tutorial ."

...