APA

(1980). 1977 economic census of outlying areas: construction industries, Puerto Rico. Washington: Dept. of Commerce, Bureau of the Census : for sale by the Supt. of Docs., U.S. Govt. Print. Off.

Chicago

1980. 1977 economic census of outlying areas: construction industries, Puerto Rico. Washington: Dept. of Commerce, Bureau of the Census : for sale by the Supt. of Docs., U.S. Govt. Print. Off.

Harvard

(1980). 1977 economic census of outlying areas: construction industries, Puerto Rico. Washington: Dept. of Commerce, Bureau of the Census : for sale by the Supt. of Docs., U.S. Govt. Print. Off.

MLA

1977 economic census of outlying areas: construction industries, Puerto Rico. Washington: Dept. of Commerce, Bureau of the Census : for sale by the Supt. of Docs., U.S. Govt. Print. Off. 1980.