Hopkins & Allen Arms Co. Fifty Years of Gunmaking 1867 - 1917 by Joseph T. Vorisek is about the best book on H&A.
Inexpensive turn of the century handgun
10-100 USD or so
Your Hopkins & Allen XL model was made between 1902-1914.These were a five shot double action.there value is not much,between 55-160 dollars.
You have to state whether it is a handgun, rifle, or shotgun and then whether it is a bolt action, semi-automatic, single action, double action or pump action.
Try Hopkins & Allen. Depending on condition, anywhere from $25-100.
Cornell publications might have what you are looking for.
50-100 USD
25-100 USD or so
model 1900 fitchburg mass usa A38473
@ 50-60s make, inexpensive.
Best bet is to look at old gun catalogs in a library.
25-100 USD