Xande, o grande : história de un menino pequeno / Teresa Noronha

Xaimaca / Ricardo Güiraldes

The X in Mexico : growth within tradition

Xaimaca / Ricardo Güiraldes

X [i.e. Decimo] Bienal de Sao Paulo, catalogo, [1969].

X [i.e. Décimo] aniversario de la Fundación Shell: agricultura, educación, ciencia, cultura, benéfico-social, 1959-1969

Wuata Wuara Raza de bronce ; Wuata Wuara

Wuata Wuara Raza de bronce ; Wuata Wuara

World without borders / [by] Lester R. Brown

World who’s who in science : a biographical dictionary of notable scientists from antiquity to the present / Editor: Allen G. Debus. Associate editors: Ronald S. Calinger [and] Edward J. Collins. Managing editor: Stephen J. Kennedy