Mary (Dean) Scarborough - Origins

Many years ago (before the internet), genealogical research involved correspondence and locating actual documents found in libraries and historical societies. Research findings were published after collaboration with relatives with common ancestors. That is where my research comes from. The major work done considering the Scarborough Family came down to me from Carolyn Wells Dauner (my second cousin) who passed in 1994. Her "Wells Family Sketches" is the major source of my research. In it she quotes the "Revolutionary Patriots of Hartford County, Maryland 1775-1783" by Henry C. Peden, which mentions Mary Scarborough having the maiden name of Dean. I have seen the records of the Falls Monthly Meeting of Friends in Bucks County 10th Month, 1744, where the marriage of Euclidus Scarborough and Mary Dean is noted. An Issac Dean is recorded in that community. As a result, it was always assumed that he was Mary's father. That assumption is not necessarily fact, so I have placed a brick wall here, not having any further documentation. (I have tried to locate that document on-line but have not been successful. I only have a pencil note about it.)
Now if we can believe that Isaac Dean of Oyster Bay, New York would deliver a single daughter to marry a Quaker in Bucks County, Pennsylvania, then we have a match.