Descripción
Notas:"Prepared in cooperation with the United States Department of State as a project of the Interdepartmental Committee on Cultural and Scientific Cooperation"
Descripción Física:v. IV (XX, 609 p., 98 p. de lám., [4] h. de mapas pleg., [3] h. pleg.) : il., mapas ; 24 cm
Bibliografía:Bibliogr.: p. 567-609