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2. Bolivian Consulate General, New York, 1926. Bolivia I, No. 1, New York, September.
3. Bolivian Consulate General, New York, 1930. Bolivia II, No. 9, New York, March–April.
4. Uber Cocapflanzungen und Cocainfabrikation in Indien;Busse;Der Tropenpflanzer,1898
5. The rise and fall and rise of cocaine in the USA;Courtwright,1995