I have contacted her twice, once by email and once by fax. I will try one last time. Thanks.

Technically, of course. I'm concerned about not infringing on copyright.

I contacted Mr. Cohen's managers over several months by email and fax, with a request to use a lyric as an epigraph for a poem in a manuscript that will soon go to the publisher. To date I have received no response. What is my next step?
Thanks for your help.