:The information regarding the 670 chemicals composing toxaphene was found in multiple sources but the most reliable one was the ATSDR toxilogical profile for toxaphene. The link to this source is http://www.atsdr.cdc.gov/ToxProfiles/tp94.pdf and can be found in the "External links" section. It is the full report from which the 3rd citation, "Toxaphene - ToxFAQs," pulls all its information and summarizes.  do you think I should provide this detailed .pdf with its own reference or leave it in the external links section?