British Association for Local History
www.balh.co.uk 

Pirton Local History Society
www.pirtonhistory.co.uk

The National Archives
www.thenationalarchives.gov.uk

Details of Hertfordshire local history societies           www.hertsdirect.org/comdirectory/comvol/herit2y/hthist3y/

Hertfordshire Archives and Local Studies
http://www.hertsdirect.org/libsleisure/heritage1/HALS/