por Sears, Francis Weston, 1898-1975 [autor] | Young, Hugh D [autor] | Garcia Garcia, Mercedes [traductor] | Hernandez Vara, Rodolfo [traductor] | Rubio Guemes, Eudaldo [colaborador] | Martens Cook, Patricio [colaborador] | Gonzalez Benites, Fabio [colaborador] | Zemansky, Mark Waldo, 1900- [autor].
por Sears, Francis Weston, 1898-1975 [autor] | Zemansky, Mark Waldo, 1900- [autor] | Young, Hugh D [autor] | Garcia Garcia, Mercedes [traductor] | Hernandez Vara, Rodolfo [traductor] | Rubio Guemes, Eudaldo [colaborador] | Mortens Cook, Patricio [colaborador] | Gonzalez Benites, Fabio [colaborador].