From the Serial Killer Hit List at http://www.mayhem.net/Crime/serial1.html:
Delfina & Maria de Jesus Gonzales (91+) These two deadly sisters ran the bordello from hell in Guanajuato, Mexico. They recruited their prostitutes through help wanted ads and killed them when they stopped pleasing the clientele. Sometimes they even killed the johns who showed up to the brothel with big wads of cash. After too many unexplained disappearances, the cops raided the premises where they found the bodies of eleven males, eighty females, and several fetuses.
[From another site -- the sisters were sentenced to 40 years in prison in 1964]
Delfina & Maria de Jesus Gonzales (91+) These two deadly sisters ran the bordello from hell in Guanajuato, Mexico. They recruited their prostitutes through help wanted ads and killed them when they stopped pleasing the clientele. Sometimes they even killed the johns who showed up to the brothel with big wads of cash. After too many unexplained disappearances, the cops raided the premises where they found the bodies of eleven males, eighty females, and several fetuses.
[From another site -- the sisters were sentenced to 40 years in prison in 1964]