Effect of sewage sludge on heavy metal concentration of spinach and lettuce in soils with different pH

Vaseghi, S., H. Shariatmadari, M. Afyuni and M. Mobli. 2001. Effect of sewage sludge on heavy metal concentration of spinach and lettuce in soils with different pH. Iranian Journal of Horticultural Science and Technology 2 (3&4): 125-142. (In Persian)