[Pollution of air by lead in Riga produced by automobiles using ethyl gasoline].
D000397:Air Pollution; D001336:Automobiles; D004787:Environmental Pollution; D005742:Gasoline; D006801:Humans; D007854:Lead; D010578:Petroleum
D005742:Gasoline; D010578:Petroleum; D007854:Lead
AIR POLLUTION; LEAD; PETROLEUM