APA (7th ed.) Citation

Blavatsky, H. P. (1961). The key to theosophy. The Theosophical Publishing House.

Chicago Style (17th ed.) Citation

Blavatsky, Helen P. The Key to Theosophy. India: The Theosophical Publishing House, 1961.

MLA (9th ed.) Citation

Blavatsky, Helen P. The Key to Theosophy. The Theosophical Publishing House, 1961.

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