Certain sections of todays' media seem to confuse 'Cluster' with 'Anti-personnel' but let's not have exactitude get in the way of a good headline....
In WWII, the German 'butterfly bombs' were dropped in a canister which then split and distributed anti-personnel bombs over a wide area ; certainly used against airfields in the UK.
A true 'Cluster bomb' was the British Cluster projectile 500lb No. 14 which consisted of 106 x 4lb incendiary bombs, which was a strategic, not strictly anti-personnel bomb.