7. SS V:56-131
8. HYP IV:79
9. We found this letter reprinted in Bihar School of Yoga's version of HYP, in the commentary for IV:105-112, p. 598. Not sure where it was originally published, though.
Most texts are in agreement regarding the functions of the five major vayus. See Wikipedia
for a longer summary, plus references.
for one version of these minor vayus, and Swami Sivapriyananda's Secret Power of Tantrik Breathing
SS II:13 notes 3.5 million nadis!
For a detailed exposition on the chakras and all their parts, see Goswami's Laya Yoga - listed and linked in the Additional Reading section
10. Information on the chakras comes from these sources:
Brennan, B. (1988). Hands of light.
Eliade, M. (1969/1990). Yoga: Immortality & freedom[2nd Ed.].
Essential Qigong. (Author, publication info unknown).
Leadbeater, C. (1973).
Mercier, P. (2007).
The chakra bible.
Mullin, G. (trans. & ed.). (2007).
The Dalai Lamas on tantra.
Shumsky, S. (2006).
Tansley, D. (2004).
Radionics & the subtle anatomy of man.
Vasu, C. (trans.). (2000).
The Siva samhita [Revised Ed.].
Woodroffe, J. (1950).
The serpent power [4th Ed.].
is what we mean by 'Russian doll'.
A good deal of the information we've included in the kosha diagram is sourced from our own exposure to various teachings over the years. First mention of the koshas in Indian spiritual literature is commonly cited as the the Taittriya Upanishad
. Shankaracharya writes on them at length in his Vedantic masterpiece, Viveka Chudamani
. Modern interpretations of the koshas are often sourced to the Theosophical writer A. Powell, who wrote a book for each of the five koshas. A decent contemporary survey of the koshas from many traditions can be found in C. Dale's The Subtle Body - see Additional Reading for link and description. Finally, see the next note for a resource for comparative analysis of different systems.
For a great comparative analysis of different systems' use of koshas (or similar concepts), see K. Wilber, Integral Psychology
(Shambhala ed., pp. 197-217)