APA
(1997). Vision - Vol.89 No.6 (1997). México: Vision Incorporated.
Chicago
1997. Vision - Vol.89 No.6 (1997). México: Vision Incorporated.
Harvard
(1997). Vision - Vol.89 No.6 (1997). México: Vision Incorporated.
MLA
Vision - Vol.89 No.6 (1997). México: Vision Incorporated. 1997.