1970s Serial Killings - Who really did them?

A convicted killer tells the Chronicle in 2011 interviews that he killed 11 girls
http://www.chron.com/news/houston-texas/article/Killer-says-he-was-brainwashed-into-slaying-girls-2187501.php#item-6397
An interactive report with excerpts from Bell's letters  and audio:

 http://www.chron.com/news/interactives/bell/

Authorities say they will investigate Bell's claims:

http://www.chron.com/news/houston-texas/article/Killer-says-he-was-brainwashed-into-slaying-girls-2187501.php#item-6397

How a "boy's" body found in 1971 could really be a  girl:

http://www.chron.com/news/houston-texas/article/Some-suspect-serial-killer-in-1971-Galveston-2078025.php