The Stanzas of Dzyan were originally released by Helena Blavatsky as part of her Secret Doctrine in the late 1800s.
It is.
It is a strange document with significant Eastern inclusions and indeed was influenced heavily by Buddhist scriptures and documents in that era.
This rough esoteric doctrine, "translated" by Blavatsky, forms one of the many bases of Theosophy.
Popular in the era regardless of her habit of being caught out conducting fraudulent seances, they purport to be of Tibetan origin.
The Stanzas of Dzyan were originally released by Helena Blavatsky as part of her Secret Doctrine in the late 1800s