Tài liệu tham khảo
1. The masters and the path
2. The science of the sacraments
3. Inner life
4. The astral plane
5. The chakras
6. The hidden side of things
7. Dream: what they do
8. Life after death
9. Man: visible and invisible
10. Beginning of the sixth root race
11. Reincarnation
12. Thought forms
13. Man: whence, how and whither