Copyright Conundrums

One of the challenges with independent publishing is figuring out for myself what’s in the public domain and what’s not as well as how the concept of fair use applies when it comes to the poems and songs I wish to quote in my novel. Apparently there’s no hard and fast definition of fair use. My copyeditor says I can quote 20 percent of the text of a poem or song without seeking permission.

If the songs and poems I wish to quote are not in the public domain, how do I go about getting permissio...