المؤلفون: Hallmark, Shauna.

الموضوعات: Traffic safety and children Iowa., Elementary schools Safety measures. Iowa, Middle schools Safety measures. Iowa, School children Transportation Safety measures. Iowa, Pedestrians Safety measures. Iowa, Sécurité routière et enfants Iowa., Écoles moyennes Sécurité Mesures. Iowa, Transport scolaire Sécurité Mesures. Iowa, Piétons Sécurité Mesures. Iowa, Elementary schools Safety measures., Pedestrians Safety measures., School children Transportation Safety measures., Traffic safety and children., Highway operations., Schools., Speed zones., Iowa.

URL: http://www.ctre.iastate.edu/reports/school_zone.pdf
http://publications.iowa.gov/id/eprint/4467