1. World food prospects: critical issues for the early twenty-first century;Pinstrup-Andersen,1999
2. An Essay on the Principle of Population;Malthus,1798
3. Experiments and Observations on Different Kinds of Airs;Priestley,1774
4. Recherches chimiques sur la végétation;de Saussere,1804
5. Theory and Practice in the Use of Fertilizers;Hear,1938