Curriculum Development Center for Science and Mathematics, S. E. C. (1977). High school science 2: Living things and their environment (1st edition.). Department of Education.
Cita Chicago (17th ed.)Curriculum Development Center for Science and Mathematics, Science Education Center. High School Science 2: Living Things and Their Environment. 1st edition. Manila: Department of Education, 1977.
Cita MLA (9th ed.)Curriculum Development Center for Science and Mathematics, Science Education Center. High School Science 2: Living Things and Their Environment. 1st edition. Department of Education, 1977.
Atenció: Aquestes cites poden no estar 100% correctes.