Sources of Scionwood of Pear Cultivars, Rootstocks, and Species in Agrucultural Experiment Stations in the United States and Canada. Journal of the American Pomological Society, [S. l.], v. 24, n. 4, p. 75–83, 1970. DOI: 10.71318/apom.1970.24.4.75. Disponível em: https://journal.americanpomological.org/index.php/jofaps/article/view/1051. Acesso em: 9 dec. 2025.