1. De Re Metallica;Agricola,1950
2. Did Slavery Pay?: Readings in the Economics of Black Slavery in the United States,1971
3. Natural Resource Economic Theory of the First Conservation Movement (1895–1927);Smith,1979
4. Epilogue: Malthusian concern from 1800 to 1962;Smith,1972
5. American agriculture 1790–1840: A symposium,1972