U. de B. Charles

• General report on the industries and commerce of Spain
• Report on the industries and commerce of Spain, 20th April, 1926
• Report on the industries and commerce of Spain, December, 1921
• Report on the industries and commerce of Spain, March, 1923
• Report on the industries and commerce of Spain, March, 1924
• Report on the industries and commerce of Spain, March, 1925