[Recovery tests of several kinds of trace metals in agricultural products with square-wave polarography].
D003300:Copper / Q000032:analysis*; D007854:Lead / Q000032:analysis*; D010945:Plants, Edible / Q000032:analysis*; D011048:Polarography; D015032:Zinc / Q000032:analysis*
D007854:Lead; D003300:Copper; D015032:Zinc