I am in a disagreement with some co-workers about cigarette smoke contaminating the air inside a vehicle. With all windows up except for the driver window which is down approximately 1 inch. The smoke appears to be directed out the window but the smell of smoke is evident in the back seat. I would like to prove the concept that even tho it appears the smoke is going out the window it is still contaminating the entire volume of air inside the vehicle. If there is an article written about this subject please kindly point me to it. Thank you.