Authors can choose to use the Creative Commons Copyright. Do you know about them? They are a group of Stanford (I think) lawyers who wrote up all the legal boilerplate to protect artist rights. Artists (authors) can choose provisions that suit them. eg. attribution required, no changes allowed, free for non-commercial use, etc. These provisions are indicated by short titles that are backed up (if necessary) by all the pages of legalese. The Creative Commons copyright is widely used and respected. I've published ten books under the CCC.