We have a simple agreement that stipulates the credit line must be used when Hirschfeld artwork is reproduced. For that we will also need a physical address and phone number.
Upon approval, we will grant permission in writing. Our Invoice/Authorization will outline the terms of the permission and any applicable fees, as well as provide a copyright/credit line, which must accompany the image. Once we have that paperwork signed and returned with payment, we can release a high-res file.
Please allow sufficient lead-time for the rights clearance process. In many instances permission can be cleared almost immediately. However, the more complex the project the more time may be required.