This is an excellent book and is available for free download on many sites including mine. There is a 2008 supplement update. the excellent publication, the first on the subject is a joint effort of the Marie Walsh Sharpe art foundation and the New York City Bar Association Art Law committee. i edited both the first book and the Supplement which include articles by lawyers expert in the field. The discussions by artists and lawyers is relevant today, notwithstanding some legal changes.William Keens is not the author of the book.