Section 131 in The Punjab Motor Vehicles Rules, 1989
131. Rear mirror
. [Section 111] - Every motor vehicle other than a road roller and other vehicle specially constructed or adapted for the construction or maintenance of roads shall be fitted either internally or externally, with a mirror so placed as to enable the driver to be or become, aware of the presence, in the rear of any other vehicle the driver of which is desirous of passing such motor vehicles.
