You CAN use Bradley as a source!!! Bradley is one of the best secondary sources to use people!!!! My Ancient History teacher (Miss Tetley, the best teacher ever) says that you can use something as a source so long as it has been published. Seeing as how Ms Bradley has had her several books published you can use them as sources. Also, just as an asside, when I say use as a source I mean like this:
The creation of the cult of Aten by Akhenaten left nothing for the traditional forms of worship. (Bradley, Ancient Egypt - Reconstructing The Past )
Where you do not necessarily have to quote directly from the text, but instead you can paraphrase. This IS alright and I DO NOT care what you say in the otherwise because I KNOW it is alright because I am having several types of tutoring!!!!!!!!!!! Anyway, I think I've ranted for long enough. BRADLEY IS QUOTABLE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!