Number 31 MD Plantation, Maine
Number 31 MD Plantation is an extinct plantation, now an unorganized territory (township) in the North Washington townships of Washington County, Maine. The Number 31 Plantation Middle Division Bingham's Penobscot Purchase was organized in 1860. It is now the unorganized territory of Township 31 MD BPP (also known as Day Block Township). 
- Maine Historical Records Survey Project, Division of Professional and Service Projects, Work Projects Administration, Counties, Cities, Towns, and Plantations of Maine: a Handbook of Incorporations, Dissolutions, and Boundary Changes (Portland, Maine: The Survey, 1940), 98 (digital p. 107). A digital version is available via a link in the FamilySearch Catalog.
- SP0234, LD 619, item 1, 124th Maine State Legislature, An Act To Rename Certain Unorganized Townships in Washington County in Maine State Legislature (accessed 14 June 2013).