Fertilizer attachment for tree-planting machine : a progress report - Starostka, R. W.; MacBride, R. E.; Hulburt, W. C. (Walter Clare),; United States. Agricultural Research Service. (Washington, DC, U.S. Dept. of Agriculture, Agricultural Research Service, 1962)
https://www.biodiversitylibrary.org/bibliography/110731
Keywords: Fertilizer equipment|Fertilizers|Planters (Agricultural machinery)|Tree planting|Trees|