APA
Blackham H., . (1968). Humanism. Middlesex-Inglaterra: Penguin Books.
Chicago
Blackham H.J, . 1968. Humanism. Middlesex-Inglaterra: Penguin Books.
Harvard
Blackham H., . (1968). Humanism. Middlesex-Inglaterra: Penguin Books.
MLA
Blackham H.J, . Humanism. Middlesex-Inglaterra: Penguin Books. 1968.