Máquinas simples
By: [by Patricio R. Alvarado and Luis Montalvo]
Publisher: National Consortia for Bilingual Education
Published: 1971
Place of publication: Fort Worth
Language: spa
Subjects: Machinery; Study and teaching
Notes: Developed by the School District of Philadelphia Instructional Services ARRIBA Bilingual Program.

For grades 7-9.
Table of contents: title: v.1. Trabajo y fuerza -v.2. Las palancas -v.3. La rueda y la polea -v.4. Otras modificaciones de la rueda -v.5. El plano inclinado.; title: Text in Spanish.