The most readable texts tend to be gunderson or leibel. It depends upon the chapter and your style personally. Perez is good for looking up ports but is too much for reading the basics. If you want to do a real favor to yourself by stinton and stanton's radiation physics guide. Learn that.
RADIATION THERAPY PLANNING. Gunilla Bentel also good.
As far as articles, anything in NEJM or JAMA on cancer, and the international journal of radiation oncology, biology and physics (red journal) are the mainstays. A REALLY great source is uptodate.com. Try to get a hospital licensing to get in. It will point you to the important articles on a given topic.
