Cita APA (7a ed.)

David, A. S. (1991). Postviral fatigue syndrome and psychiatry. [s.n.].

Cita Chicago Style (17a ed.)

David, A. S. Postviral Fatigue Syndrome and Psychiatry. [S.l.]: [s.n.], 1991.

Cita MLA (9a ed.)

David, A. S. Postviral Fatigue Syndrome and Psychiatry. [s.n.], 1991.