Alfred Percy Sinnett (1840-1921): (2.2), 2, 6, 1.

(i) British (UK) Theosophist.
(ii)
Esoteric Buddhism (1883) is based entirely on the Mahatma letters he received through
Helena Blavatsky [aka
The Mahatma Letters to A.P. Sinnett ]—according to Helena Roerich.