What is wallacea?

Tania is writing a paper for her history teacher about living conditions of immigrants in urban tenements during the 19th century what sources would be the best for her to quote in?

The Gangs of New York: An Informal History of the Underworld, by Herbert AsburyGotham: a history of New York City to 1898, By Edwin G. Burrows, Mike WallaceA city of immigrants: dreams and realities of life in New York, 1840-2007, By LaGuardia Community College. LaGuardia and Wagner Archives, Richard K. LiebermanGerman New York City, By Richard PanchykThe Promised City: New York's Jews, 1870-1914, by Moses RischinShutting Out the Sky: Life in the Tenements of New York, 1880-1924, by Deborah HopkinsonTenement: Immmigrant Life on the Lower East Side, by Raymond Bial(Some of the books I took off this list are very good books on their topic, but are not relevant to the 19th century experience.)Also see the link below.