APA (7th ed.) Citation

Parker, D., & Parker, H. (1982). The secret sect. D. Parker.

Chicago Style (17th ed.) Citation

Parker, Doug, and Helen Parker. The Secret Sect. Pendle Hill, N.S.W., Australia: D. Parker, 1982.

MLA (8th ed.) Citation

Parker, Doug, and Helen Parker. The Secret Sect. D. Parker, 1982.