The coldest case in modern times

Jack the Ripper killed 11 women, most of them in 1888. He was never caught by police. All the women were prostitutes, heavy drinkers, killed in the early morning hours, manually strangulated and had some body-organs removed (kidney,nose,heart, and sexual organs) showing some anatomical knowledge by the killer.
After 100 a complete profile (published however only on these days) was made by FBI SSA John Douglas.
What a shame the profiler has not given the name of the coldest case in the whole crime's serial story.
To know more on this:
http://www.dailymail.co.uk/news/article-1378432/Jack-Ripper-FBI-dossier-reveals-chilling-profile-released-100-years-late.html