# Appendix ## Exhibit A: Eligible tax group, type, and code [Click this link](https://docs.digitalriver.com/digital-river-api/product-management/creating-and-updating-skus#tax-code) to learn which tax codes are available in the Digital River API. A Digital River account is required to use this extension. If you do not have a Digital River account, you can sign up for one [here](https://dashboard.digitalriver.com/signup). ## Exhibit B: Sequence diagram {% file src="" %}