Nakagawa, João, Cláudio Cavariani, Claudemir Zucareli, and Juliane Dossi Salum. 2008. “Hard Seeds Ocurrence During Velvet Bean Maturation”. Científica 34 (1). Dracena, SP:107-14. https://doi.org/10.15361/1984-5529.2006v34n1p107 - 114.