School Mathematics Study Group & Schaaf, W. L. (1967). Nature and history of Pi. Leland Stanford Junior University.
Citazione stile Chigago Style (17a edizione)School Mathematics Study Group e William L. Schaaf. Nature and History of Pi. Stanford, CA: Leland Stanford Junior University, 1967.
Citatione MLA (9a ed.)School Mathematics Study Group e William L. Schaaf. Nature and History of Pi. Leland Stanford Junior University, 1967.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.