from American Heritage magazine "I have been in a house in 5th Street with Mr. Key. How many times I don’t know..."
arlingtoncemetery.net
from [United States government. "Daniel Edgar Sickles Major General, United States Army". Arlington National Cemetery National Website. Retrieved July 28, 2016.]: "His ambition to fit himself for the diplomatic service had led him to take up the study of French and Italian, and in this way he met Therese Bagioli, daughter of an Italian music teacher." (other sources say he knew her since infancy)
from assumption.eduArchived September 14, 2006, at the Wayback Machine "The stories told how Sickles had received an anonymous letter on Thursday, February 24th, informing him of his wife's relationship with Key."
from assumption.eduArchived September 14, 2006, at the Wayback Machine "The stories told how Sickles had received an anonymous letter on Thursday, February 24th, informing him of his wife's relationship with Key."