16th census of the United States: 1940. Población. Boletín núm. 1-[3] ... Puerto Rico.

Nos. 2-3 have title: Censo décimosexto de los Estados Unidos: 1940.Puerto Rico. Población ....

Annual book on statistics of Puerto Rico.

Mode of access: Internet.

Report of Northwest Experiment Station, Crookston.

Mode of access: Internet.

Bulletins of the Agricultural Experiment Station, University of Illinois.

Mode of access: Internet.

Annual report of the University of Wyoming Agricultural Experiment Station.

Report year ends June 30.

Bulletin - Maine Agricultural Experiment Station.

Mode of access: Internet.

Hydrologic study. Western Division, South Coast Irrigation District for Puerto Rico Water Resources Authority,

Mode of access: Internet.

Prehistoria de Puerto Rico

Mode of access: Internet.

La isla de Puerto-Rico (primera parte) : bosquejo histórico, desde la conquista hasta principios de 1891 /

"Apéndice: Organización política, económica y administrativa de Puerto Rico. Legislación vigente en 1891": p. [2-5] at end.

Parnaso antillano : compilación completa de los mejores poetas de Cuba, Puerto Rico y Santo Domingo /

Mode of access: Internet.

Annual report - College of Agriculture, Agricultural Experiment Station of the University of Kentucky.

Issue for 1910 includes also: Report of the director of the Kentucky Agricultural Experiment Station to the Governer of Kentucky on the enforcement of the Food and drugs act for the years 1908 and 1909.

Puerto Rico: su ambiente geográfico; manual de geografía de Puerto Rico para séptimo grado

Includes bibliographies.

Bulletin - University of Hawaii, Agricultural Experiment Station.

Some numbers issued out of chronological sequence.

Report on surveys, research projects, investigations and other organized fact-gathering activities of the Government of Puerto Rico.

Mode of access: Internet.

Status of Puerto Rico : report of the United States-Puerto Rico Commission on the Status of Puerto Rico, August, 1966.

Mode of access: Internet.