A license from the rightsholder allows you to use their material, which otherwise would be a violation of federal law.
license agreement
Copyright gives the creator of a work control over its use. A license is a way the copyright owner can allow others to use the work.
With a license, yes. Without a license, no.
The copyright holder or an appointed administrator can issue a license.
One must apply to the copyright holder for permisson to use their copyrighted item.
With a license from the copyright holders, yes.
That phrase could mean several things. It could refer to a letter that is protected by copyright, or a letter allowing use of someone's copyright (i.e., a license).
It's written permission from the copyright holder letting someone else use the material; it's usually quite specific. On the other hand, a Creative Commons license is a type of license, and it's extraordinarily broad.
For the most part, you would license your specific use rather than attempting to purchase rights for the entire series. To license a work, contact the copyright holder in writing, explaining your proposed use in detail.
In order to use copyright-protected materials that are not your own original work, you need permission from the rightsholder; this is usually in the form of a license, which can be as broad as a Creative Commons license or (more often) specific to your proposed use.
The short answer is, you ask the copyright holder. The long answer is, it depends on the type of work, and your proposed use. For some uses, you can get a blanket license from a royalty collecting society that will cover thousands of works for a given period of time. For others, you will need to negotiate directly with the rightsholder for a license, which will be very specific to your use.
You may only use images that are your own original work, in the public domain, or for which you have a license from the copyright holder.