“Performance of ‘Gala’ Apple on Four Semi-Dwarf Rootstocks: A Ten-Year Summary of the 1994 NC-140 Semi-Dwarf Rootstock Trial”. Journal of the American Pomological Society, vol. 60, no. 2, Apr. 2006, pp. 58-68, https://doi.org/10.71318/apom.2006.60.2.58.