If you are recruiting students, professionals or volunteers to help create multi-media content for your books such as videos, images or recordings you first need to ensure you have the correct permissions from any participants involved in the production of the materials. Please make sure content creators seek permissions from video and audio etc. participants before production commences. You also need to make sure that you know exactly how the creators want to share their work from the outset. For example, you may be commissioning a graphic designer to create a book cover who does not want to use a creative commons license, and you will have to gain permissions for use. Here is an agreement form you can adapt for your own purposes before you formalise any content creation.