Παραπομπή APA

Keatinge, R. (1997). Cyclists should wear helmets. Better to control the demand for fast cars.

Παραπομπή Chicago Style

Keatinge, R. Cyclists Should Wear Helmets. Better to Control the Demand for Fast Cars. 1997.

Παραπομπή MLA

Keatinge, R. Cyclists Should Wear Helmets. Better to Control the Demand for Fast Cars. 1997.

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