Fortifications
- Pillboxes UK
- Fort Siloso.com
- The Penang Battery
- Penang Battery photos : Private collection
- Pulau Sejahat photos : Private collection

- Pillbox Study Group
- UK Forts Club
- Defence of Cumbria in the 20th Century
- WW2 & Cold War History in Britain
- Heugh Gun Battery
- Military Ruins

Far East WW2 related
- Far Eastern Heroes
- National Malaya & Borneo Veterans Association
- The Virgin Soldiers
- Children of Far East Prisoners of War
- Far East Prisoners of War community
- Britain at war
- Burma Star Association
- Kranji War & Military Cemeteries
- S1942 BATTLEFIELD SINGAPORE
- Changi Museum
- The Wartime Memories Project
- My Far East
- Malayan Volunteers Group
- Singapore Evacuation 1942
- Malaya historical group

Museums and archives
- The National Archives UK
- Australian War Memorial
- National Archives of Australia
- National Archives of Singapore
- Firepower : James Clavell library
- IWM Collections Online
- National Archives of Malaysia