Cita APA (7a ed.)

Chen, I. (1939). An Empirical Study of Verbal, Numerical, and Spatial Factors in Mental Organization. Principia press.

Cita Chicago Style (17a ed.)

Chen, Isidor. An Empirical Study of Verbal, Numerical, and Spatial Factors in Mental Organization. Indiana: Principia press, 1939.

Cita MLA (9a ed.)

Chen, Isidor. An Empirical Study of Verbal, Numerical, and Spatial Factors in Mental Organization. Principia press, 1939.