This pair of 1979 Mexican airmail stamps commemorates the Cincuentenario de la Autonomía de la Universidad Nacional (50th Anniversary of the Autonomy of the National University). The 4.30 peso stamp, designed by David Alfaro Siqueiros, depicts “Estudiantes que extienden sus brazos a la cultura” (“Students Extending Their Arms Toward Culture”), symbolizing the spirit of intellectual and cultural outreach. The 1.60 peso stamp by José Chávez Morado shows “Retorno de Quetzalcóatl” (“Return of Quetzalcoatl”), representing the rebirth of knowledge and Mexican identity through ancient wisdom. Together, these stamps celebrate Mexico’s commitment to education, art, and national heritage through powerful muralist imagery.