There were two good articles on Frank Hollenbeck in The Gun Report -- one by Al Atterbury in 1989 and one by H.J. Swinney in 1991. Along about 1902-03 you could find ads in magazines for four different guns that owed something of their designs to Frank A. Hollenbeck -- Baker, Syracuse Arms Co., Baltimore Arms Co. and the Hollenbeck Gun Co. Frank also worked with W.H. Baker in Lisle, NY, and later with Baker and L.C. Smith in Syracuse. Some very early Hollenbeck hammer guns exist marked Lisle, NY.

I'm in Kodiak, far from my canned responses for these questions, so this is the best I can do from memory.