Vallandigham, Paul. "Flintlocks: How to Shoot Them". GUNS AND SHOOTING ONLINE Muzzleloader and Black Powder Information. Archived from the original on 25 August 2015. Retrieved 16 August 2015.
"Alarm-clock". Hermitage Projects - Resotoration Programme. The State Hermitage Museum. Archived from the original on 14 March 2014. Retrieved 14 March 2014.
Vallandigham, Paul. "Flintlocks: How to Shoot Them". GUNS AND SHOOTING ONLINE Muzzleloader and Black Powder Information. Archived from the original on 25 August 2015. Retrieved 16 August 2015.
"Alarm-clock". Hermitage Projects - Resotoration Programme. The State Hermitage Museum. Archived from the original on 14 March 2014. Retrieved 14 March 2014.