APA (7th ed.) Citation

Blavatsky, H. P. (1921). The secret doctrine: The synthesis of science, religion, and philosophy / by H. P. Blavatsky. The Theosophical Publ. House.

Chicago Style (17th ed.) Citation

Blavatsky, Helena P. The Secret Doctrine: The Synthesis of Science, Religion, and Philosophy / by H. P. Blavatsky. London: The Theosophical Publ. House, 1921.

MLA (8th ed.) Citation

Blavatsky, Helena P. The Secret Doctrine: The Synthesis of Science, Religion, and Philosophy / by H. P. Blavatsky. The Theosophical Publ. House, 1921.

Warning: These citations may not always be 100% accurate.