This primary source comes from the Records of the Bureau of the Census.
Full Citation: Population Density of Puerto Rico by Census Tract (Spanish); 2010; [Decennial] Census of Population and Housing, 2010: Thematic Maps, Record Set; Thematic Maps from the 23rd Census of Population and Housing, 2010 - 2010; Records of the Bureau of the Census, Record Group 29; National Archives at College Park, College Park, MD. [Online Version, https://docsteach.org/documents/document/2010-profile-map-population-density-puerto-rico-spanish, February 9, 2025]