A Historical record of all the foot regiments of the British Army by H L Wickes, Osprey 1974, is available as a .pdf and can be downloaded for free: https://www.ebooksmagz.com/view/regim...f-all-the.html. This is an invaluable source if you are searching for info about one of the old foot regiments.

There is also a companion volume of all the regiments of horse.

Owl