Cita APA (7a ed.)

Lewis, D. G. (1959). Bilingualism and non-verbal intelligence: A further study of test results. [s.n.].

Cita Chicago Style (17a ed.)

Lewis, D. G. Bilingualism and Non-verbal Intelligence: A Further Study of Test Results. [S.l.]: [s.n.], 1959.

Cita MLA (9a ed.)

Lewis, D. G. Bilingualism and Non-verbal Intelligence: A Further Study of Test Results. [s.n.], 1959.