Ancestry.com - Massachusetts Census, 1790-1890
AIS indexes. Original source: Jackson, Ron V., Accelerated Indexing Systems, comp.. Massachusetts Census, 1790-1890 [database on-line]. Provo, UT, USA: Ancestry.com Operations Inc, 1999. Original data: Compiled and digitized by Mr. Jackson and AIS from microfilmed schedules of the U.S. Federal Decennial Census, territorial/state censuses, and/or census substitutes.