An abridgement of 'The secret doctrine'

MLA

Blavatsky, H. P, and Christmas Humphreys. An Abridgement of 'the Secret Doctrine'. London: Theosophical Publishing House, 1966.

APA

Blavatsky, H. P, & Humphreys, C. (1966). An abridgement of 'The secret doctrine'. London: Theosophical Publishing House.

Chicago

Blavatsky, H. P. ed., and Christmas Humphreys ed. An Abridgement of 'the Secret Doctrine'. London: Theosophical Publishing House, 1966.