Sheffield, L. J. (2003). Extending the challenge in mathematics: Developing mathematical promise in K-8 students. Corwin Press.
Čikaški stil citiranja (17. izdanje)Sheffield, Linda Jensen. Extending the Challenge in Mathematics: Developing Mathematical Promise in K-8 Students. Thousand Oaks, CA: Corwin Press, 2003.
MLA način citiranja (8. izdanje)Sheffield, Linda Jensen. Extending the Challenge in Mathematics: Developing Mathematical Promise in K-8 Students. Corwin Press, 2003.
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