Marco, You'll see in skepth's comment below that the Teacher's writings are extensive and not all at these links. What he means by BI is "Brethren Information", a sort of lesson unit. Processeans in training attended sessions called "Progresses" with a long O; these were sessions to read and study the numbered BI's on the Gods, contact, healing, telepathy, and other topics. I'm not sure where you would find all of the BI's. Regarding the "occult", I have to say I never heard that word used around The Process. Telepathy, for example, was treated as a natural skill to be validated, expressed, and thereby developed. In telepathy sessions, we did psychometry: we would take turns holding an object to our foreheads and talking freely about the impressions we got; this would be understood as the vibrations coming from someone the object had belonged to.