Sé el primero en recomendar esto
Chief Obstacles chosen by incarnating souls - Michael Teachings. This document is chapter 23 from the following book, and each obstacle is examined in detail in chapter 24 in Shepherd Hoodwin - Journey of Your Soul ( Source: https://www.amazon.com/Journey-Your-Soul-Explores-Teachings-ebook/dp/B008IS1ZUU ).
At the end of that chapter, Mr. Hoodwin recommends the following book:
"Transforming Your Dragons: Turning Personality Fear Patterns into Personal Power" by Jose Stevens is an excellent book devoted entirely to obstacles ( https://www.amazon.com/gp/offer-listing/1879181177/ref=sr_1_1_olp?ie=UTF8&qid=1521922632 ).