Experiences using statecharts for a system requirements specification. - Nancy G. Leveson; Mats P. E. Heimdahl; Holly Hildreth; Jon Damon Reese; R. Ortega (IWSSD, 1991)

Characterization of a Temperature Gradient System for Phantom Studies in Hyperthermia Therapy. - E. Hernández; E. Trujillo; F. Cortes; R. Ortega; Arturo Vera; Lorenzo Leija (CCE, 2023)

Circularization in the Damped Kepler Problem. - K. Uldall Kristiansen; R. Ortega (SIAM J. Appl. Dyn. Syst., 2024)