From The Seattle Times:

When Green River killer Gary L. Ridgway was sentenced to life imprisonment in 2003 for the murders of 48 Seattle-area women, four of his victims were identified only as "Jane Doe."

Yesterday, more than 1-1/2 years later, investigators made a plea to the public to help identify the four victims, known only as bones 10, 16, 17 and 20. They are asking individuals who may know about people who went missing in King County in the 1970s and 1980s to contact them.