United States. Bureau of the Census. (1994). 1990 census of population and housing: Summary tape file 1B, extract on CD-ROM (Puerto Rico): technical documentation. Bureau of the Census.
Chicago Style (17th ed.) CitationUnited States. Bureau of the Census. 1990 Census of Population and Housing: Summary Tape File 1B, Extract on CD-ROM (Puerto Rico): Technical Documentation. [Washington, D.C.]: Bureau of the Census, 1994.
MLA (9th ed.) CitationUnited States. Bureau of the Census. 1990 Census of Population and Housing: Summary Tape File 1B, Extract on CD-ROM (Puerto Rico): Technical Documentation. Bureau of the Census, 1994.
Warning: These citations may not always be 100% accurate.