I'm a spanish dreamer and only a few books (some of Stephen LaBerge) are translated to my language. I read Castaneda, Stephen LaBerge and some spanish authors. Then, I started to read in english Robert Waggoner's 'Gateway to the inner self' and I enjoyed it so much. I prefer to read book with theories and documented explorations instead books with the basic knowledge on lucid dreaming. Could you recommend me some advanced lucid dreaming book like that?