How many delegates signed the declaration of independence?

Of the approximately fifty delegates who are thought to have been present in Congress during the voting on independence in early July 1776, eight never signed the Declaration: John Alsop, George Clinton, John Dickinson, Charles Humphreys, Robert R. Livingston, John Rogers, Thomas Willing, and Henry Wisner.
So 42 signed 8 did not

He gathered information from primary sources.