• 3 Ethnology
• 1 Boundaries
• 1 Coal
• 1 Coal mines and mining
• 1 Electric lines
• 1 Electric power-plants
• 1 Gas industry
• 1 History
• 1 Macedonian question
• 1 Natural gas pipelines
• 1 Nuclear power plants
• 1 Petroleum industry and trade
• 1 Petroleum pipelines
• 1 Territorial questions
• 1 Transportation
• 1 World War, 1914-1918

• 12 Europe, Central
• 4 Europe, Eastern
• 1 Italy

• 23 Maps
• 2 Government publications
• 2 Outline maps
• 2 Physical maps

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