1. The study of removal methods of heavy metals from sludge;Lo,1985
2. Variables affecting metal removal from sludge;Wozniak;J. Water Pollut. Control Fed.,1984
3. Sources of metals in New York city wastewater;Klein;J. Water Pollut. Control Fed.,1974
4. Heavy metals in wastewater in three urban areas;Davis;J. Water Pollut. Control Fed.,1975
5. Impact of pretreatment on sludge content of heavy metal;Koch;Water Pollut. Control Fed.,1982