revision preference src: In two books, Peter Haining argued that Sweeney Todd was a historical figure who committed his crimes around 1800. Nevertheless, other researchers who have tried to verify his citations find nothing in these sources to back Haining's claims. <SEP> tgt: In two books, Peter Haining argued that Sweeney Todd was a historical figure who committed his crimes around 1800. Other researchers who have tried to verify Sweeney Todd's citations find nothing in these sources to Peter Haining Haining's claims.